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e74abb32 XL |
1 | use super::*; |
2 | use crate::punctuated::Punctuated; | |
3 | #[cfg(feature = "extra-traits")] | |
4 | use crate::tt::TokenStreamHelper; | |
5 | use proc_macro2::{Span, TokenStream}; | |
60c5eb7d XL |
6 | #[cfg(feature = "printing")] |
7 | use quote::IdentFragment; | |
8 | #[cfg(feature = "printing")] | |
9 | use std::fmt::{self, Display}; | |
e74abb32 XL |
10 | use std::hash::{Hash, Hasher}; |
11 | #[cfg(all(feature = "parsing", feature = "full"))] | |
12 | use std::mem; | |
13 | ||
14 | ast_enum_of_structs! { | |
15 | /// A Rust expression. | |
16 | /// | |
17 | /// *This type is available if Syn is built with the `"derive"` or `"full"` | |
18 | /// feature.* | |
19 | /// | |
20 | /// # Syntax tree enums | |
21 | /// | |
22 | /// This type is a syntax tree enum. In Syn this and other syntax tree enums | |
23 | /// are designed to be traversed using the following rebinding idiom. | |
24 | /// | |
25 | /// ``` | |
26 | /// # use syn::Expr; | |
27 | /// # | |
28 | /// # fn example(expr: Expr) { | |
29 | /// # const IGNORE: &str = stringify! { | |
30 | /// let expr: Expr = /* ... */; | |
31 | /// # }; | |
32 | /// match expr { | |
33 | /// Expr::MethodCall(expr) => { | |
34 | /// /* ... */ | |
35 | /// } | |
36 | /// Expr::Cast(expr) => { | |
37 | /// /* ... */ | |
38 | /// } | |
39 | /// Expr::If(expr) => { | |
40 | /// /* ... */ | |
41 | /// } | |
42 | /// | |
43 | /// /* ... */ | |
44 | /// # _ => {} | |
45 | /// # } | |
46 | /// # } | |
47 | /// ``` | |
48 | /// | |
49 | /// We begin with a variable `expr` of type `Expr` that has no fields | |
50 | /// (because it is an enum), and by matching on it and rebinding a variable | |
51 | /// with the same name `expr` we effectively imbue our variable with all of | |
52 | /// the data fields provided by the variant that it turned out to be. So for | |
53 | /// example above if we ended up in the `MethodCall` case then we get to use | |
54 | /// `expr.receiver`, `expr.args` etc; if we ended up in the `If` case we get | |
55 | /// to use `expr.cond`, `expr.then_branch`, `expr.else_branch`. | |
56 | /// | |
57 | /// This approach avoids repeating the variant names twice on every line. | |
58 | /// | |
59 | /// ``` | |
60 | /// # use syn::{Expr, ExprMethodCall}; | |
61 | /// # | |
62 | /// # fn example(expr: Expr) { | |
63 | /// // Repetitive; recommend not doing this. | |
64 | /// match expr { | |
65 | /// Expr::MethodCall(ExprMethodCall { method, args, .. }) => { | |
66 | /// # } | |
67 | /// # _ => {} | |
68 | /// # } | |
69 | /// # } | |
70 | /// ``` | |
71 | /// | |
72 | /// In general, the name to which a syntax tree enum variant is bound should | |
73 | /// be a suitable name for the complete syntax tree enum type. | |
74 | /// | |
75 | /// ``` | |
76 | /// # use syn::{Expr, ExprField}; | |
77 | /// # | |
78 | /// # fn example(discriminant: ExprField) { | |
79 | /// // Binding is called `base` which is the name I would use if I were | |
80 | /// // assigning `*discriminant.base` without an `if let`. | |
81 | /// if let Expr::Tuple(base) = *discriminant.base { | |
82 | /// # } | |
83 | /// # } | |
84 | /// ``` | |
85 | /// | |
86 | /// A sign that you may not be choosing the right variable names is if you | |
87 | /// see names getting repeated in your code, like accessing | |
88 | /// `receiver.receiver` or `pat.pat` or `cond.cond`. | |
89 | pub enum Expr #manual_extra_traits { | |
90 | /// A slice literal expression: `[a, b, c, d]`. | |
91 | Array(ExprArray), | |
92 | ||
93 | /// An assignment expression: `a = compute()`. | |
94 | Assign(ExprAssign), | |
95 | ||
96 | /// A compound assignment expression: `counter += 1`. | |
97 | AssignOp(ExprAssignOp), | |
98 | ||
99 | /// An async block: `async { ... }`. | |
100 | Async(ExprAsync), | |
101 | ||
102 | /// An await expression: `fut.await`. | |
103 | Await(ExprAwait), | |
104 | ||
105 | /// A binary operation: `a + b`, `a * b`. | |
106 | Binary(ExprBinary), | |
107 | ||
108 | /// A blocked scope: `{ ... }`. | |
109 | Block(ExprBlock), | |
110 | ||
111 | /// A box expression: `box f`. | |
112 | Box(ExprBox), | |
113 | ||
114 | /// A `break`, with an optional label to break and an optional | |
115 | /// expression. | |
116 | Break(ExprBreak), | |
117 | ||
118 | /// A function call expression: `invoke(a, b)`. | |
119 | Call(ExprCall), | |
120 | ||
121 | /// A cast expression: `foo as f64`. | |
122 | Cast(ExprCast), | |
123 | ||
124 | /// A closure expression: `|a, b| a + b`. | |
125 | Closure(ExprClosure), | |
126 | ||
127 | /// A `continue`, with an optional label. | |
128 | Continue(ExprContinue), | |
129 | ||
130 | /// Access of a named struct field (`obj.k`) or unnamed tuple struct | |
131 | /// field (`obj.0`). | |
132 | Field(ExprField), | |
133 | ||
134 | /// A for loop: `for pat in expr { ... }`. | |
135 | ForLoop(ExprForLoop), | |
136 | ||
137 | /// An expression contained within invisible delimiters. | |
138 | /// | |
139 | /// This variant is important for faithfully representing the precedence | |
140 | /// of expressions and is related to `None`-delimited spans in a | |
141 | /// `TokenStream`. | |
142 | Group(ExprGroup), | |
143 | ||
144 | /// An `if` expression with an optional `else` block: `if expr { ... } | |
145 | /// else { ... }`. | |
146 | /// | |
147 | /// The `else` branch expression may only be an `If` or `Block` | |
148 | /// expression, not any of the other types of expression. | |
149 | If(ExprIf), | |
150 | ||
151 | /// A square bracketed indexing expression: `vector[2]`. | |
152 | Index(ExprIndex), | |
153 | ||
154 | /// A `let` guard: `let Some(x) = opt`. | |
155 | Let(ExprLet), | |
156 | ||
157 | /// A literal in place of an expression: `1`, `"foo"`. | |
158 | Lit(ExprLit), | |
159 | ||
160 | /// Conditionless loop: `loop { ... }`. | |
161 | Loop(ExprLoop), | |
162 | ||
163 | /// A macro invocation expression: `format!("{}", q)`. | |
164 | Macro(ExprMacro), | |
165 | ||
166 | /// A `match` expression: `match n { Some(n) => {}, None => {} }`. | |
167 | Match(ExprMatch), | |
168 | ||
169 | /// A method call expression: `x.foo::<T>(a, b)`. | |
170 | MethodCall(ExprMethodCall), | |
171 | ||
172 | /// A parenthesized expression: `(a + b)`. | |
173 | Paren(ExprParen), | |
174 | ||
175 | /// A path like `std::mem::replace` possibly containing generic | |
176 | /// parameters and a qualified self-type. | |
177 | /// | |
178 | /// A plain identifier like `x` is a path of length 1. | |
179 | Path(ExprPath), | |
180 | ||
181 | /// A range expression: `1..2`, `1..`, `..2`, `1..=2`, `..=2`. | |
182 | Range(ExprRange), | |
183 | ||
184 | /// A referencing operation: `&a` or `&mut a`. | |
185 | Reference(ExprReference), | |
186 | ||
187 | /// An array literal constructed from one repeated element: `[0u8; N]`. | |
188 | Repeat(ExprRepeat), | |
189 | ||
190 | /// A `return`, with an optional value to be returned. | |
191 | Return(ExprReturn), | |
192 | ||
193 | /// A struct literal expression: `Point { x: 1, y: 1 }`. | |
194 | /// | |
195 | /// The `rest` provides the value of the remaining fields as in `S { a: | |
196 | /// 1, b: 1, ..rest }`. | |
197 | Struct(ExprStruct), | |
198 | ||
199 | /// A try-expression: `expr?`. | |
200 | Try(ExprTry), | |
201 | ||
202 | /// A try block: `try { ... }`. | |
203 | TryBlock(ExprTryBlock), | |
204 | ||
205 | /// A tuple expression: `(a, b, c, d)`. | |
206 | Tuple(ExprTuple), | |
207 | ||
208 | /// A type ascription expression: `foo: f64`. | |
209 | Type(ExprType), | |
210 | ||
211 | /// A unary operation: `!x`, `*x`. | |
212 | Unary(ExprUnary), | |
213 | ||
214 | /// An unsafe block: `unsafe { ... }`. | |
215 | Unsafe(ExprUnsafe), | |
216 | ||
217 | /// Tokens in expression position not interpreted by Syn. | |
218 | Verbatim(TokenStream), | |
219 | ||
220 | /// A while loop: `while expr { ... }`. | |
221 | While(ExprWhile), | |
222 | ||
223 | /// A yield expression: `yield expr`. | |
224 | Yield(ExprYield), | |
225 | ||
226 | #[doc(hidden)] | |
227 | __Nonexhaustive, | |
228 | } | |
229 | } | |
230 | ||
231 | ast_struct! { | |
232 | /// A slice literal expression: `[a, b, c, d]`. | |
233 | /// | |
234 | /// *This type is available if Syn is built with the `"full"` feature.* | |
235 | pub struct ExprArray #full { | |
236 | pub attrs: Vec<Attribute>, | |
237 | pub bracket_token: token::Bracket, | |
238 | pub elems: Punctuated<Expr, Token![,]>, | |
239 | } | |
240 | } | |
241 | ||
242 | ast_struct! { | |
243 | /// An assignment expression: `a = compute()`. | |
244 | /// | |
245 | /// *This type is available if Syn is built with the `"full"` feature.* | |
246 | pub struct ExprAssign #full { | |
247 | pub attrs: Vec<Attribute>, | |
248 | pub left: Box<Expr>, | |
249 | pub eq_token: Token![=], | |
250 | pub right: Box<Expr>, | |
251 | } | |
252 | } | |
253 | ||
254 | ast_struct! { | |
255 | /// A compound assignment expression: `counter += 1`. | |
256 | /// | |
257 | /// *This type is available if Syn is built with the `"full"` feature.* | |
258 | pub struct ExprAssignOp #full { | |
259 | pub attrs: Vec<Attribute>, | |
260 | pub left: Box<Expr>, | |
261 | pub op: BinOp, | |
262 | pub right: Box<Expr>, | |
263 | } | |
264 | } | |
265 | ||
266 | ast_struct! { | |
267 | /// An async block: `async { ... }`. | |
268 | /// | |
269 | /// *This type is available if Syn is built with the `"full"` feature.* | |
270 | pub struct ExprAsync #full { | |
271 | pub attrs: Vec<Attribute>, | |
272 | pub async_token: Token![async], | |
273 | pub capture: Option<Token![move]>, | |
274 | pub block: Block, | |
275 | } | |
276 | } | |
277 | ||
278 | ast_struct! { | |
279 | /// An await expression: `fut.await`. | |
280 | /// | |
281 | /// *This type is available if Syn is built with the `"full"` feature.* | |
282 | pub struct ExprAwait #full { | |
283 | pub attrs: Vec<Attribute>, | |
284 | pub base: Box<Expr>, | |
285 | pub dot_token: Token![.], | |
286 | pub await_token: token::Await, | |
287 | } | |
288 | } | |
289 | ||
290 | ast_struct! { | |
291 | /// A binary operation: `a + b`, `a * b`. | |
292 | /// | |
293 | /// *This type is available if Syn is built with the `"derive"` or | |
294 | /// `"full"` feature.* | |
295 | pub struct ExprBinary { | |
296 | pub attrs: Vec<Attribute>, | |
297 | pub left: Box<Expr>, | |
298 | pub op: BinOp, | |
299 | pub right: Box<Expr>, | |
300 | } | |
301 | } | |
302 | ||
303 | ast_struct! { | |
304 | /// A blocked scope: `{ ... }`. | |
305 | /// | |
306 | /// *This type is available if Syn is built with the `"full"` feature.* | |
307 | pub struct ExprBlock #full { | |
308 | pub attrs: Vec<Attribute>, | |
309 | pub label: Option<Label>, | |
310 | pub block: Block, | |
311 | } | |
312 | } | |
313 | ||
314 | ast_struct! { | |
315 | /// A box expression: `box f`. | |
316 | /// | |
317 | /// *This type is available if Syn is built with the `"full"` feature.* | |
318 | pub struct ExprBox #full { | |
319 | pub attrs: Vec<Attribute>, | |
320 | pub box_token: Token![box], | |
321 | pub expr: Box<Expr>, | |
322 | } | |
323 | } | |
324 | ||
325 | ast_struct! { | |
326 | /// A `break`, with an optional label to break and an optional | |
327 | /// expression. | |
328 | /// | |
329 | /// *This type is available if Syn is built with the `"full"` feature.* | |
330 | pub struct ExprBreak #full { | |
331 | pub attrs: Vec<Attribute>, | |
332 | pub break_token: Token![break], | |
333 | pub label: Option<Lifetime>, | |
334 | pub expr: Option<Box<Expr>>, | |
335 | } | |
336 | } | |
337 | ||
338 | ast_struct! { | |
339 | /// A function call expression: `invoke(a, b)`. | |
340 | /// | |
341 | /// *This type is available if Syn is built with the `"derive"` or | |
342 | /// `"full"` feature.* | |
343 | pub struct ExprCall { | |
344 | pub attrs: Vec<Attribute>, | |
345 | pub func: Box<Expr>, | |
346 | pub paren_token: token::Paren, | |
347 | pub args: Punctuated<Expr, Token![,]>, | |
348 | } | |
349 | } | |
350 | ||
351 | ast_struct! { | |
352 | /// A cast expression: `foo as f64`. | |
353 | /// | |
354 | /// *This type is available if Syn is built with the `"derive"` or | |
355 | /// `"full"` feature.* | |
356 | pub struct ExprCast { | |
357 | pub attrs: Vec<Attribute>, | |
358 | pub expr: Box<Expr>, | |
359 | pub as_token: Token![as], | |
360 | pub ty: Box<Type>, | |
361 | } | |
362 | } | |
363 | ||
364 | ast_struct! { | |
365 | /// A closure expression: `|a, b| a + b`. | |
366 | /// | |
367 | /// *This type is available if Syn is built with the `"full"` feature.* | |
368 | pub struct ExprClosure #full { | |
369 | pub attrs: Vec<Attribute>, | |
370 | pub asyncness: Option<Token![async]>, | |
371 | pub movability: Option<Token![static]>, | |
372 | pub capture: Option<Token![move]>, | |
373 | pub or1_token: Token![|], | |
374 | pub inputs: Punctuated<Pat, Token![,]>, | |
375 | pub or2_token: Token![|], | |
376 | pub output: ReturnType, | |
377 | pub body: Box<Expr>, | |
378 | } | |
379 | } | |
380 | ||
381 | ast_struct! { | |
382 | /// A `continue`, with an optional label. | |
383 | /// | |
384 | /// *This type is available if Syn is built with the `"full"` feature.* | |
385 | pub struct ExprContinue #full { | |
386 | pub attrs: Vec<Attribute>, | |
387 | pub continue_token: Token![continue], | |
388 | pub label: Option<Lifetime>, | |
389 | } | |
390 | } | |
391 | ||
392 | ast_struct! { | |
393 | /// Access of a named struct field (`obj.k`) or unnamed tuple struct | |
394 | /// field (`obj.0`). | |
395 | /// | |
396 | /// *This type is available if Syn is built with the `"full"` feature.* | |
397 | pub struct ExprField { | |
398 | pub attrs: Vec<Attribute>, | |
399 | pub base: Box<Expr>, | |
400 | pub dot_token: Token![.], | |
401 | pub member: Member, | |
402 | } | |
403 | } | |
404 | ||
405 | ast_struct! { | |
406 | /// A for loop: `for pat in expr { ... }`. | |
407 | /// | |
408 | /// *This type is available if Syn is built with the `"full"` feature.* | |
409 | pub struct ExprForLoop #full { | |
410 | pub attrs: Vec<Attribute>, | |
411 | pub label: Option<Label>, | |
412 | pub for_token: Token![for], | |
413 | pub pat: Pat, | |
414 | pub in_token: Token![in], | |
415 | pub expr: Box<Expr>, | |
416 | pub body: Block, | |
417 | } | |
418 | } | |
419 | ||
420 | ast_struct! { | |
421 | /// An expression contained within invisible delimiters. | |
422 | /// | |
423 | /// This variant is important for faithfully representing the precedence | |
424 | /// of expressions and is related to `None`-delimited spans in a | |
425 | /// `TokenStream`. | |
426 | /// | |
427 | /// *This type is available if Syn is built with the `"full"` feature.* | |
428 | pub struct ExprGroup #full { | |
429 | pub attrs: Vec<Attribute>, | |
430 | pub group_token: token::Group, | |
431 | pub expr: Box<Expr>, | |
432 | } | |
433 | } | |
434 | ||
435 | ast_struct! { | |
436 | /// An `if` expression with an optional `else` block: `if expr { ... } | |
437 | /// else { ... }`. | |
438 | /// | |
439 | /// The `else` branch expression may only be an `If` or `Block` | |
440 | /// expression, not any of the other types of expression. | |
441 | /// | |
442 | /// *This type is available if Syn is built with the `"full"` feature.* | |
443 | pub struct ExprIf #full { | |
444 | pub attrs: Vec<Attribute>, | |
445 | pub if_token: Token![if], | |
446 | pub cond: Box<Expr>, | |
447 | pub then_branch: Block, | |
448 | pub else_branch: Option<(Token![else], Box<Expr>)>, | |
449 | } | |
450 | } | |
451 | ||
452 | ast_struct! { | |
453 | /// A square bracketed indexing expression: `vector[2]`. | |
454 | /// | |
455 | /// *This type is available if Syn is built with the `"derive"` or | |
456 | /// `"full"` feature.* | |
457 | pub struct ExprIndex { | |
458 | pub attrs: Vec<Attribute>, | |
459 | pub expr: Box<Expr>, | |
460 | pub bracket_token: token::Bracket, | |
461 | pub index: Box<Expr>, | |
462 | } | |
463 | } | |
464 | ||
465 | ast_struct! { | |
466 | /// A `let` guard: `let Some(x) = opt`. | |
467 | /// | |
468 | /// *This type is available if Syn is built with the `"full"` feature.* | |
469 | pub struct ExprLet #full { | |
470 | pub attrs: Vec<Attribute>, | |
471 | pub let_token: Token![let], | |
472 | pub pat: Pat, | |
473 | pub eq_token: Token![=], | |
474 | pub expr: Box<Expr>, | |
475 | } | |
476 | } | |
477 | ||
478 | ast_struct! { | |
479 | /// A literal in place of an expression: `1`, `"foo"`. | |
480 | /// | |
481 | /// *This type is available if Syn is built with the `"derive"` or | |
482 | /// `"full"` feature.* | |
483 | pub struct ExprLit { | |
484 | pub attrs: Vec<Attribute>, | |
485 | pub lit: Lit, | |
486 | } | |
487 | } | |
488 | ||
489 | ast_struct! { | |
490 | /// Conditionless loop: `loop { ... }`. | |
491 | /// | |
492 | /// *This type is available if Syn is built with the `"full"` feature.* | |
493 | pub struct ExprLoop #full { | |
494 | pub attrs: Vec<Attribute>, | |
495 | pub label: Option<Label>, | |
496 | pub loop_token: Token![loop], | |
497 | pub body: Block, | |
498 | } | |
499 | } | |
500 | ||
501 | ast_struct! { | |
502 | /// A macro invocation expression: `format!("{}", q)`. | |
503 | /// | |
504 | /// *This type is available if Syn is built with the `"full"` feature.* | |
505 | pub struct ExprMacro #full { | |
506 | pub attrs: Vec<Attribute>, | |
507 | pub mac: Macro, | |
508 | } | |
509 | } | |
510 | ||
511 | ast_struct! { | |
512 | /// A `match` expression: `match n { Some(n) => {}, None => {} }`. | |
513 | /// | |
514 | /// *This type is available if Syn is built with the `"full"` feature.* | |
515 | pub struct ExprMatch #full { | |
516 | pub attrs: Vec<Attribute>, | |
517 | pub match_token: Token![match], | |
518 | pub expr: Box<Expr>, | |
519 | pub brace_token: token::Brace, | |
520 | pub arms: Vec<Arm>, | |
521 | } | |
522 | } | |
523 | ||
524 | ast_struct! { | |
525 | /// A method call expression: `x.foo::<T>(a, b)`. | |
526 | /// | |
527 | /// *This type is available if Syn is built with the `"full"` feature.* | |
528 | pub struct ExprMethodCall #full { | |
529 | pub attrs: Vec<Attribute>, | |
530 | pub receiver: Box<Expr>, | |
531 | pub dot_token: Token![.], | |
532 | pub method: Ident, | |
533 | pub turbofish: Option<MethodTurbofish>, | |
534 | pub paren_token: token::Paren, | |
535 | pub args: Punctuated<Expr, Token![,]>, | |
536 | } | |
537 | } | |
538 | ||
539 | ast_struct! { | |
540 | /// A parenthesized expression: `(a + b)`. | |
541 | /// | |
542 | /// *This type is available if Syn is built with the `"full"` feature.* | |
543 | pub struct ExprParen { | |
544 | pub attrs: Vec<Attribute>, | |
545 | pub paren_token: token::Paren, | |
546 | pub expr: Box<Expr>, | |
547 | } | |
548 | } | |
549 | ||
550 | ast_struct! { | |
551 | /// A path like `std::mem::replace` possibly containing generic | |
552 | /// parameters and a qualified self-type. | |
553 | /// | |
554 | /// A plain identifier like `x` is a path of length 1. | |
555 | /// | |
556 | /// *This type is available if Syn is built with the `"derive"` or | |
557 | /// `"full"` feature.* | |
558 | pub struct ExprPath { | |
559 | pub attrs: Vec<Attribute>, | |
560 | pub qself: Option<QSelf>, | |
561 | pub path: Path, | |
562 | } | |
563 | } | |
564 | ||
565 | ast_struct! { | |
566 | /// A range expression: `1..2`, `1..`, `..2`, `1..=2`, `..=2`. | |
567 | /// | |
568 | /// *This type is available if Syn is built with the `"full"` feature.* | |
569 | pub struct ExprRange #full { | |
570 | pub attrs: Vec<Attribute>, | |
571 | pub from: Option<Box<Expr>>, | |
572 | pub limits: RangeLimits, | |
573 | pub to: Option<Box<Expr>>, | |
574 | } | |
575 | } | |
576 | ||
577 | ast_struct! { | |
578 | /// A referencing operation: `&a` or `&mut a`. | |
579 | /// | |
580 | /// *This type is available if Syn is built with the `"full"` feature.* | |
581 | pub struct ExprReference #full { | |
582 | pub attrs: Vec<Attribute>, | |
583 | pub and_token: Token![&], | |
584 | pub raw: Reserved, | |
585 | pub mutability: Option<Token![mut]>, | |
586 | pub expr: Box<Expr>, | |
587 | } | |
588 | } | |
589 | ||
590 | ast_struct! { | |
591 | /// An array literal constructed from one repeated element: `[0u8; N]`. | |
592 | /// | |
593 | /// *This type is available if Syn is built with the `"full"` feature.* | |
594 | pub struct ExprRepeat #full { | |
595 | pub attrs: Vec<Attribute>, | |
596 | pub bracket_token: token::Bracket, | |
597 | pub expr: Box<Expr>, | |
598 | pub semi_token: Token![;], | |
599 | pub len: Box<Expr>, | |
600 | } | |
601 | } | |
602 | ||
603 | ast_struct! { | |
604 | /// A `return`, with an optional value to be returned. | |
605 | /// | |
606 | /// *This type is available if Syn is built with the `"full"` feature.* | |
607 | pub struct ExprReturn #full { | |
608 | pub attrs: Vec<Attribute>, | |
609 | pub return_token: Token![return], | |
610 | pub expr: Option<Box<Expr>>, | |
611 | } | |
612 | } | |
613 | ||
614 | ast_struct! { | |
615 | /// A struct literal expression: `Point { x: 1, y: 1 }`. | |
616 | /// | |
617 | /// The `rest` provides the value of the remaining fields as in `S { a: | |
618 | /// 1, b: 1, ..rest }`. | |
619 | /// | |
620 | /// *This type is available if Syn is built with the `"full"` feature.* | |
621 | pub struct ExprStruct #full { | |
622 | pub attrs: Vec<Attribute>, | |
623 | pub path: Path, | |
624 | pub brace_token: token::Brace, | |
625 | pub fields: Punctuated<FieldValue, Token![,]>, | |
626 | pub dot2_token: Option<Token![..]>, | |
627 | pub rest: Option<Box<Expr>>, | |
628 | } | |
629 | } | |
630 | ||
631 | ast_struct! { | |
632 | /// A try-expression: `expr?`. | |
633 | /// | |
634 | /// *This type is available if Syn is built with the `"full"` feature.* | |
635 | pub struct ExprTry #full { | |
636 | pub attrs: Vec<Attribute>, | |
637 | pub expr: Box<Expr>, | |
638 | pub question_token: Token![?], | |
639 | } | |
640 | } | |
641 | ||
642 | ast_struct! { | |
643 | /// A try block: `try { ... }`. | |
644 | /// | |
645 | /// *This type is available if Syn is built with the `"full"` feature.* | |
646 | pub struct ExprTryBlock #full { | |
647 | pub attrs: Vec<Attribute>, | |
648 | pub try_token: Token![try], | |
649 | pub block: Block, | |
650 | } | |
651 | } | |
652 | ||
653 | ast_struct! { | |
654 | /// A tuple expression: `(a, b, c, d)`. | |
655 | /// | |
656 | /// *This type is available if Syn is built with the `"full"` feature.* | |
657 | pub struct ExprTuple #full { | |
658 | pub attrs: Vec<Attribute>, | |
659 | pub paren_token: token::Paren, | |
660 | pub elems: Punctuated<Expr, Token![,]>, | |
661 | } | |
662 | } | |
663 | ||
664 | ast_struct! { | |
665 | /// A type ascription expression: `foo: f64`. | |
666 | /// | |
667 | /// *This type is available if Syn is built with the `"full"` feature.* | |
668 | pub struct ExprType #full { | |
669 | pub attrs: Vec<Attribute>, | |
670 | pub expr: Box<Expr>, | |
671 | pub colon_token: Token![:], | |
672 | pub ty: Box<Type>, | |
673 | } | |
674 | } | |
675 | ||
676 | ast_struct! { | |
677 | /// A unary operation: `!x`, `*x`. | |
678 | /// | |
679 | /// *This type is available if Syn is built with the `"derive"` or | |
680 | /// `"full"` feature.* | |
681 | pub struct ExprUnary { | |
682 | pub attrs: Vec<Attribute>, | |
683 | pub op: UnOp, | |
684 | pub expr: Box<Expr>, | |
685 | } | |
686 | } | |
687 | ||
688 | ast_struct! { | |
689 | /// An unsafe block: `unsafe { ... }`. | |
690 | /// | |
691 | /// *This type is available if Syn is built with the `"full"` feature.* | |
692 | pub struct ExprUnsafe #full { | |
693 | pub attrs: Vec<Attribute>, | |
694 | pub unsafe_token: Token![unsafe], | |
695 | pub block: Block, | |
696 | } | |
697 | } | |
698 | ||
699 | ast_struct! { | |
700 | /// A while loop: `while expr { ... }`. | |
701 | /// | |
702 | /// *This type is available if Syn is built with the `"full"` feature.* | |
703 | pub struct ExprWhile #full { | |
704 | pub attrs: Vec<Attribute>, | |
705 | pub label: Option<Label>, | |
706 | pub while_token: Token![while], | |
707 | pub cond: Box<Expr>, | |
708 | pub body: Block, | |
709 | } | |
710 | } | |
711 | ||
712 | ast_struct! { | |
713 | /// A yield expression: `yield expr`. | |
714 | /// | |
715 | /// *This type is available if Syn is built with the `"full"` feature.* | |
716 | pub struct ExprYield #full { | |
717 | pub attrs: Vec<Attribute>, | |
718 | pub yield_token: Token![yield], | |
719 | pub expr: Option<Box<Expr>>, | |
720 | } | |
721 | } | |
722 | ||
723 | #[cfg(feature = "extra-traits")] | |
724 | impl Eq for Expr {} | |
725 | ||
726 | #[cfg(feature = "extra-traits")] | |
727 | impl PartialEq for Expr { | |
728 | fn eq(&self, other: &Self) -> bool { | |
729 | match (self, other) { | |
730 | (Expr::Array(this), Expr::Array(other)) => this == other, | |
731 | (Expr::Assign(this), Expr::Assign(other)) => this == other, | |
732 | (Expr::AssignOp(this), Expr::AssignOp(other)) => this == other, | |
733 | (Expr::Async(this), Expr::Async(other)) => this == other, | |
734 | (Expr::Await(this), Expr::Await(other)) => this == other, | |
735 | (Expr::Binary(this), Expr::Binary(other)) => this == other, | |
736 | (Expr::Block(this), Expr::Block(other)) => this == other, | |
737 | (Expr::Box(this), Expr::Box(other)) => this == other, | |
738 | (Expr::Break(this), Expr::Break(other)) => this == other, | |
739 | (Expr::Call(this), Expr::Call(other)) => this == other, | |
740 | (Expr::Cast(this), Expr::Cast(other)) => this == other, | |
741 | (Expr::Closure(this), Expr::Closure(other)) => this == other, | |
742 | (Expr::Continue(this), Expr::Continue(other)) => this == other, | |
743 | (Expr::Field(this), Expr::Field(other)) => this == other, | |
744 | (Expr::ForLoop(this), Expr::ForLoop(other)) => this == other, | |
745 | (Expr::Group(this), Expr::Group(other)) => this == other, | |
746 | (Expr::If(this), Expr::If(other)) => this == other, | |
747 | (Expr::Index(this), Expr::Index(other)) => this == other, | |
748 | (Expr::Let(this), Expr::Let(other)) => this == other, | |
749 | (Expr::Lit(this), Expr::Lit(other)) => this == other, | |
750 | (Expr::Loop(this), Expr::Loop(other)) => this == other, | |
751 | (Expr::Macro(this), Expr::Macro(other)) => this == other, | |
752 | (Expr::Match(this), Expr::Match(other)) => this == other, | |
753 | (Expr::MethodCall(this), Expr::MethodCall(other)) => this == other, | |
754 | (Expr::Paren(this), Expr::Paren(other)) => this == other, | |
755 | (Expr::Path(this), Expr::Path(other)) => this == other, | |
756 | (Expr::Range(this), Expr::Range(other)) => this == other, | |
757 | (Expr::Reference(this), Expr::Reference(other)) => this == other, | |
758 | (Expr::Repeat(this), Expr::Repeat(other)) => this == other, | |
759 | (Expr::Return(this), Expr::Return(other)) => this == other, | |
760 | (Expr::Struct(this), Expr::Struct(other)) => this == other, | |
761 | (Expr::Try(this), Expr::Try(other)) => this == other, | |
762 | (Expr::TryBlock(this), Expr::TryBlock(other)) => this == other, | |
763 | (Expr::Tuple(this), Expr::Tuple(other)) => this == other, | |
764 | (Expr::Type(this), Expr::Type(other)) => this == other, | |
765 | (Expr::Unary(this), Expr::Unary(other)) => this == other, | |
766 | (Expr::Unsafe(this), Expr::Unsafe(other)) => this == other, | |
767 | (Expr::Verbatim(this), Expr::Verbatim(other)) => { | |
768 | TokenStreamHelper(this) == TokenStreamHelper(other) | |
769 | } | |
770 | (Expr::While(this), Expr::While(other)) => this == other, | |
771 | (Expr::Yield(this), Expr::Yield(other)) => this == other, | |
772 | _ => false, | |
773 | } | |
774 | } | |
775 | } | |
776 | ||
777 | #[cfg(feature = "extra-traits")] | |
778 | impl Hash for Expr { | |
779 | fn hash<H>(&self, hash: &mut H) | |
780 | where | |
781 | H: Hasher, | |
782 | { | |
783 | match self { | |
784 | Expr::Array(expr) => { | |
785 | hash.write_u8(0); | |
786 | expr.hash(hash); | |
787 | } | |
788 | Expr::Assign(expr) => { | |
789 | hash.write_u8(1); | |
790 | expr.hash(hash); | |
791 | } | |
792 | Expr::AssignOp(expr) => { | |
793 | hash.write_u8(2); | |
794 | expr.hash(hash); | |
795 | } | |
796 | Expr::Async(expr) => { | |
797 | hash.write_u8(3); | |
798 | expr.hash(hash); | |
799 | } | |
800 | Expr::Await(expr) => { | |
801 | hash.write_u8(4); | |
802 | expr.hash(hash); | |
803 | } | |
804 | Expr::Binary(expr) => { | |
805 | hash.write_u8(5); | |
806 | expr.hash(hash); | |
807 | } | |
808 | Expr::Block(expr) => { | |
809 | hash.write_u8(6); | |
810 | expr.hash(hash); | |
811 | } | |
812 | Expr::Box(expr) => { | |
813 | hash.write_u8(7); | |
814 | expr.hash(hash); | |
815 | } | |
816 | Expr::Break(expr) => { | |
817 | hash.write_u8(8); | |
818 | expr.hash(hash); | |
819 | } | |
820 | Expr::Call(expr) => { | |
821 | hash.write_u8(9); | |
822 | expr.hash(hash); | |
823 | } | |
824 | Expr::Cast(expr) => { | |
825 | hash.write_u8(10); | |
826 | expr.hash(hash); | |
827 | } | |
828 | Expr::Closure(expr) => { | |
829 | hash.write_u8(11); | |
830 | expr.hash(hash); | |
831 | } | |
832 | Expr::Continue(expr) => { | |
833 | hash.write_u8(12); | |
834 | expr.hash(hash); | |
835 | } | |
836 | Expr::Field(expr) => { | |
837 | hash.write_u8(13); | |
838 | expr.hash(hash); | |
839 | } | |
840 | Expr::ForLoop(expr) => { | |
841 | hash.write_u8(14); | |
842 | expr.hash(hash); | |
843 | } | |
844 | Expr::Group(expr) => { | |
845 | hash.write_u8(15); | |
846 | expr.hash(hash); | |
847 | } | |
848 | Expr::If(expr) => { | |
849 | hash.write_u8(16); | |
850 | expr.hash(hash); | |
851 | } | |
852 | Expr::Index(expr) => { | |
853 | hash.write_u8(17); | |
854 | expr.hash(hash); | |
855 | } | |
856 | Expr::Let(expr) => { | |
857 | hash.write_u8(18); | |
858 | expr.hash(hash); | |
859 | } | |
860 | Expr::Lit(expr) => { | |
861 | hash.write_u8(19); | |
862 | expr.hash(hash); | |
863 | } | |
864 | Expr::Loop(expr) => { | |
865 | hash.write_u8(20); | |
866 | expr.hash(hash); | |
867 | } | |
868 | Expr::Macro(expr) => { | |
869 | hash.write_u8(21); | |
870 | expr.hash(hash); | |
871 | } | |
872 | Expr::Match(expr) => { | |
873 | hash.write_u8(22); | |
874 | expr.hash(hash); | |
875 | } | |
876 | Expr::MethodCall(expr) => { | |
877 | hash.write_u8(23); | |
878 | expr.hash(hash); | |
879 | } | |
880 | Expr::Paren(expr) => { | |
881 | hash.write_u8(24); | |
882 | expr.hash(hash); | |
883 | } | |
884 | Expr::Path(expr) => { | |
885 | hash.write_u8(25); | |
886 | expr.hash(hash); | |
887 | } | |
888 | Expr::Range(expr) => { | |
889 | hash.write_u8(26); | |
890 | expr.hash(hash); | |
891 | } | |
892 | Expr::Reference(expr) => { | |
893 | hash.write_u8(27); | |
894 | expr.hash(hash); | |
895 | } | |
896 | Expr::Repeat(expr) => { | |
897 | hash.write_u8(28); | |
898 | expr.hash(hash); | |
899 | } | |
900 | Expr::Return(expr) => { | |
901 | hash.write_u8(29); | |
902 | expr.hash(hash); | |
903 | } | |
904 | Expr::Struct(expr) => { | |
905 | hash.write_u8(30); | |
906 | expr.hash(hash); | |
907 | } | |
908 | Expr::Try(expr) => { | |
909 | hash.write_u8(31); | |
910 | expr.hash(hash); | |
911 | } | |
912 | Expr::TryBlock(expr) => { | |
913 | hash.write_u8(32); | |
914 | expr.hash(hash); | |
915 | } | |
916 | Expr::Tuple(expr) => { | |
917 | hash.write_u8(33); | |
918 | expr.hash(hash); | |
919 | } | |
920 | Expr::Type(expr) => { | |
921 | hash.write_u8(34); | |
922 | expr.hash(hash); | |
923 | } | |
924 | Expr::Unary(expr) => { | |
925 | hash.write_u8(35); | |
926 | expr.hash(hash); | |
927 | } | |
928 | Expr::Unsafe(expr) => { | |
929 | hash.write_u8(36); | |
930 | expr.hash(hash); | |
931 | } | |
932 | Expr::Verbatim(expr) => { | |
933 | hash.write_u8(37); | |
934 | TokenStreamHelper(expr).hash(hash); | |
935 | } | |
936 | Expr::While(expr) => { | |
937 | hash.write_u8(38); | |
938 | expr.hash(hash); | |
939 | } | |
940 | Expr::Yield(expr) => { | |
941 | hash.write_u8(39); | |
942 | expr.hash(hash); | |
943 | } | |
944 | Expr::__Nonexhaustive => unreachable!(), | |
945 | } | |
946 | } | |
947 | } | |
948 | ||
949 | impl Expr { | |
950 | #[cfg(all(feature = "parsing", feature = "full"))] | |
951 | pub(crate) fn replace_attrs(&mut self, new: Vec<Attribute>) -> Vec<Attribute> { | |
952 | match self { | |
953 | Expr::Box(ExprBox { attrs, .. }) | |
954 | | Expr::Array(ExprArray { attrs, .. }) | |
955 | | Expr::Call(ExprCall { attrs, .. }) | |
956 | | Expr::MethodCall(ExprMethodCall { attrs, .. }) | |
957 | | Expr::Tuple(ExprTuple { attrs, .. }) | |
958 | | Expr::Binary(ExprBinary { attrs, .. }) | |
959 | | Expr::Unary(ExprUnary { attrs, .. }) | |
960 | | Expr::Lit(ExprLit { attrs, .. }) | |
961 | | Expr::Cast(ExprCast { attrs, .. }) | |
962 | | Expr::Type(ExprType { attrs, .. }) | |
963 | | Expr::Let(ExprLet { attrs, .. }) | |
964 | | Expr::If(ExprIf { attrs, .. }) | |
965 | | Expr::While(ExprWhile { attrs, .. }) | |
966 | | Expr::ForLoop(ExprForLoop { attrs, .. }) | |
967 | | Expr::Loop(ExprLoop { attrs, .. }) | |
968 | | Expr::Match(ExprMatch { attrs, .. }) | |
969 | | Expr::Closure(ExprClosure { attrs, .. }) | |
970 | | Expr::Unsafe(ExprUnsafe { attrs, .. }) | |
971 | | Expr::Block(ExprBlock { attrs, .. }) | |
972 | | Expr::Assign(ExprAssign { attrs, .. }) | |
973 | | Expr::AssignOp(ExprAssignOp { attrs, .. }) | |
974 | | Expr::Field(ExprField { attrs, .. }) | |
975 | | Expr::Index(ExprIndex { attrs, .. }) | |
976 | | Expr::Range(ExprRange { attrs, .. }) | |
977 | | Expr::Path(ExprPath { attrs, .. }) | |
978 | | Expr::Reference(ExprReference { attrs, .. }) | |
979 | | Expr::Break(ExprBreak { attrs, .. }) | |
980 | | Expr::Continue(ExprContinue { attrs, .. }) | |
981 | | Expr::Return(ExprReturn { attrs, .. }) | |
982 | | Expr::Macro(ExprMacro { attrs, .. }) | |
983 | | Expr::Struct(ExprStruct { attrs, .. }) | |
984 | | Expr::Repeat(ExprRepeat { attrs, .. }) | |
985 | | Expr::Paren(ExprParen { attrs, .. }) | |
986 | | Expr::Group(ExprGroup { attrs, .. }) | |
987 | | Expr::Try(ExprTry { attrs, .. }) | |
988 | | Expr::Async(ExprAsync { attrs, .. }) | |
989 | | Expr::Await(ExprAwait { attrs, .. }) | |
990 | | Expr::TryBlock(ExprTryBlock { attrs, .. }) | |
991 | | Expr::Yield(ExprYield { attrs, .. }) => mem::replace(attrs, new), | |
992 | Expr::Verbatim(_) => Vec::new(), | |
993 | Expr::__Nonexhaustive => unreachable!(), | |
994 | } | |
995 | } | |
996 | } | |
997 | ||
998 | ast_enum! { | |
999 | /// A struct or tuple struct field accessed in a struct literal or field | |
1000 | /// expression. | |
1001 | /// | |
1002 | /// *This type is available if Syn is built with the `"derive"` or `"full"` | |
1003 | /// feature.* | |
60c5eb7d XL |
1004 | #[derive(Eq, PartialEq, Hash)] |
1005 | pub enum Member #manual_extra_traits { | |
e74abb32 XL |
1006 | /// A named field like `self.x`. |
1007 | Named(Ident), | |
1008 | /// An unnamed field like `self.0`. | |
1009 | Unnamed(Index), | |
1010 | } | |
1011 | } | |
1012 | ||
60c5eb7d XL |
1013 | #[cfg(feature = "printing")] |
1014 | impl IdentFragment for Member { | |
1015 | fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { | |
1016 | match self { | |
1017 | Member::Named(m) => Display::fmt(m, formatter), | |
1018 | Member::Unnamed(m) => Display::fmt(&m.index, formatter), | |
1019 | } | |
1020 | } | |
1021 | ||
1022 | fn span(&self) -> Option<Span> { | |
1023 | match self { | |
1024 | Member::Named(m) => Some(m.span()), | |
1025 | Member::Unnamed(m) => Some(m.span), | |
1026 | } | |
1027 | } | |
1028 | } | |
1029 | ||
e74abb32 XL |
1030 | ast_struct! { |
1031 | /// The index of an unnamed tuple struct field. | |
1032 | /// | |
1033 | /// *This type is available if Syn is built with the `"derive"` or `"full"` | |
1034 | /// feature.* | |
1035 | pub struct Index #manual_extra_traits { | |
1036 | pub index: u32, | |
1037 | pub span: Span, | |
1038 | } | |
1039 | } | |
1040 | ||
1041 | impl From<usize> for Index { | |
1042 | fn from(index: usize) -> Index { | |
1043 | assert!(index < u32::max_value() as usize); | |
1044 | Index { | |
1045 | index: index as u32, | |
1046 | span: Span::call_site(), | |
1047 | } | |
1048 | } | |
1049 | } | |
1050 | ||
e74abb32 XL |
1051 | impl Eq for Index {} |
1052 | ||
e74abb32 XL |
1053 | impl PartialEq for Index { |
1054 | fn eq(&self, other: &Self) -> bool { | |
1055 | self.index == other.index | |
1056 | } | |
1057 | } | |
1058 | ||
e74abb32 XL |
1059 | impl Hash for Index { |
1060 | fn hash<H: Hasher>(&self, state: &mut H) { | |
1061 | self.index.hash(state); | |
1062 | } | |
1063 | } | |
1064 | ||
60c5eb7d XL |
1065 | #[cfg(feature = "printing")] |
1066 | impl IdentFragment for Index { | |
1067 | fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { | |
1068 | Display::fmt(&self.index, formatter) | |
1069 | } | |
1070 | ||
1071 | fn span(&self) -> Option<Span> { | |
1072 | Some(self.span) | |
1073 | } | |
1074 | } | |
1075 | ||
e74abb32 XL |
1076 | #[cfg(feature = "full")] |
1077 | ast_struct! { | |
1078 | #[derive(Default)] | |
1079 | pub struct Reserved { | |
60c5eb7d | 1080 | _private: (), |
e74abb32 XL |
1081 | } |
1082 | } | |
1083 | ||
1084 | #[cfg(feature = "full")] | |
1085 | ast_struct! { | |
1086 | /// The `::<>` explicit type parameters passed to a method call: | |
1087 | /// `parse::<u64>()`. | |
1088 | /// | |
1089 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1090 | pub struct MethodTurbofish { | |
1091 | pub colon2_token: Token![::], | |
1092 | pub lt_token: Token![<], | |
1093 | pub args: Punctuated<GenericMethodArgument, Token![,]>, | |
1094 | pub gt_token: Token![>], | |
1095 | } | |
1096 | } | |
1097 | ||
1098 | #[cfg(feature = "full")] | |
1099 | ast_enum! { | |
1100 | /// An individual generic argument to a method, like `T`. | |
1101 | /// | |
1102 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1103 | pub enum GenericMethodArgument { | |
1104 | /// A type argument. | |
1105 | Type(Type), | |
1106 | /// A const expression. Must be inside of a block. | |
1107 | /// | |
1108 | /// NOTE: Identity expressions are represented as Type arguments, as | |
1109 | /// they are indistinguishable syntactically. | |
1110 | Const(Expr), | |
1111 | } | |
1112 | } | |
1113 | ||
1114 | #[cfg(feature = "full")] | |
1115 | ast_struct! { | |
1116 | /// A field-value pair in a struct literal. | |
1117 | /// | |
1118 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1119 | pub struct FieldValue { | |
1120 | /// Attributes tagged on the field. | |
1121 | pub attrs: Vec<Attribute>, | |
1122 | ||
1123 | /// Name or index of the field. | |
1124 | pub member: Member, | |
1125 | ||
1126 | /// The colon in `Struct { x: x }`. If written in shorthand like | |
1127 | /// `Struct { x }`, there is no colon. | |
1128 | pub colon_token: Option<Token![:]>, | |
1129 | ||
1130 | /// Value of the field. | |
1131 | pub expr: Expr, | |
1132 | } | |
1133 | } | |
1134 | ||
1135 | #[cfg(feature = "full")] | |
1136 | ast_struct! { | |
1137 | /// A lifetime labeling a `for`, `while`, or `loop`. | |
1138 | /// | |
1139 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1140 | pub struct Label { | |
1141 | pub name: Lifetime, | |
1142 | pub colon_token: Token![:], | |
1143 | } | |
1144 | } | |
1145 | ||
1146 | #[cfg(feature = "full")] | |
1147 | ast_struct! { | |
1148 | /// One arm of a `match` expression: `0...10 => { return true; }`. | |
1149 | /// | |
1150 | /// As in: | |
1151 | /// | |
1152 | /// ``` | |
1153 | /// # fn f() -> bool { | |
1154 | /// # let n = 0; | |
1155 | /// match n { | |
1156 | /// 0...10 => { | |
1157 | /// return true; | |
1158 | /// } | |
1159 | /// // ... | |
1160 | /// # _ => {} | |
1161 | /// } | |
1162 | /// # false | |
1163 | /// # } | |
1164 | /// ``` | |
1165 | /// | |
1166 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1167 | pub struct Arm { | |
1168 | pub attrs: Vec<Attribute>, | |
1169 | pub pat: Pat, | |
1170 | pub guard: Option<(Token![if], Box<Expr>)>, | |
1171 | pub fat_arrow_token: Token![=>], | |
1172 | pub body: Box<Expr>, | |
1173 | pub comma: Option<Token![,]>, | |
1174 | } | |
1175 | } | |
1176 | ||
1177 | #[cfg(feature = "full")] | |
1178 | ast_enum! { | |
1179 | /// Limit types of a range, inclusive or exclusive. | |
1180 | /// | |
1181 | /// *This type is available if Syn is built with the `"full"` feature.* | |
1182 | #[cfg_attr(feature = "clone-impls", derive(Copy))] | |
1183 | pub enum RangeLimits { | |
1184 | /// Inclusive at the beginning, exclusive at the end. | |
1185 | HalfOpen(Token![..]), | |
1186 | /// Inclusive at the beginning and end. | |
1187 | Closed(Token![..=]), | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | #[cfg(any(feature = "parsing", feature = "printing"))] | |
1192 | #[cfg(feature = "full")] | |
1193 | pub(crate) fn requires_terminator(expr: &Expr) -> bool { | |
1194 | // see https://github.com/rust-lang/rust/blob/eb8f2586e/src/libsyntax/parse/classify.rs#L17-L37 | |
1195 | match *expr { | |
1196 | Expr::Unsafe(..) | |
1197 | | Expr::Block(..) | |
1198 | | Expr::If(..) | |
1199 | | Expr::Match(..) | |
1200 | | Expr::While(..) | |
1201 | | Expr::Loop(..) | |
1202 | | Expr::ForLoop(..) | |
1203 | | Expr::Async(..) | |
1204 | | Expr::TryBlock(..) => false, | |
1205 | _ => true, | |
1206 | } | |
1207 | } | |
1208 | ||
1209 | #[cfg(feature = "parsing")] | |
1210 | pub(crate) mod parsing { | |
1211 | use super::*; | |
1212 | ||
1213 | use crate::parse::{Parse, ParseStream, Result}; | |
1214 | use crate::path; | |
1215 | ||
1216 | // When we're parsing expressions which occur before blocks, like in an if | |
1217 | // statement's condition, we cannot parse a struct literal. | |
1218 | // | |
1219 | // Struct literals are ambiguous in certain positions | |
1220 | // https://github.com/rust-lang/rfcs/pull/92 | |
1221 | #[derive(Copy, Clone)] | |
1222 | pub struct AllowStruct(bool); | |
1223 | ||
1224 | #[derive(Copy, Clone, PartialEq, PartialOrd)] | |
1225 | enum Precedence { | |
1226 | Any, | |
1227 | Assign, | |
1228 | Range, | |
1229 | Or, | |
1230 | And, | |
1231 | Compare, | |
1232 | BitOr, | |
1233 | BitXor, | |
1234 | BitAnd, | |
1235 | Shift, | |
1236 | Arithmetic, | |
1237 | Term, | |
1238 | Cast, | |
1239 | } | |
1240 | ||
1241 | impl Precedence { | |
1242 | fn of(op: &BinOp) -> Self { | |
1243 | match *op { | |
1244 | BinOp::Add(_) | BinOp::Sub(_) => Precedence::Arithmetic, | |
1245 | BinOp::Mul(_) | BinOp::Div(_) | BinOp::Rem(_) => Precedence::Term, | |
1246 | BinOp::And(_) => Precedence::And, | |
1247 | BinOp::Or(_) => Precedence::Or, | |
1248 | BinOp::BitXor(_) => Precedence::BitXor, | |
1249 | BinOp::BitAnd(_) => Precedence::BitAnd, | |
1250 | BinOp::BitOr(_) => Precedence::BitOr, | |
1251 | BinOp::Shl(_) | BinOp::Shr(_) => Precedence::Shift, | |
1252 | BinOp::Eq(_) | |
1253 | | BinOp::Lt(_) | |
1254 | | BinOp::Le(_) | |
1255 | | BinOp::Ne(_) | |
1256 | | BinOp::Ge(_) | |
1257 | | BinOp::Gt(_) => Precedence::Compare, | |
1258 | BinOp::AddEq(_) | |
1259 | | BinOp::SubEq(_) | |
1260 | | BinOp::MulEq(_) | |
1261 | | BinOp::DivEq(_) | |
1262 | | BinOp::RemEq(_) | |
1263 | | BinOp::BitXorEq(_) | |
1264 | | BinOp::BitAndEq(_) | |
1265 | | BinOp::BitOrEq(_) | |
1266 | | BinOp::ShlEq(_) | |
1267 | | BinOp::ShrEq(_) => Precedence::Assign, | |
1268 | } | |
1269 | } | |
1270 | } | |
1271 | ||
1272 | impl Parse for Expr { | |
1273 | fn parse(input: ParseStream) -> Result<Self> { | |
1274 | ambiguous_expr(input, AllowStruct(true)) | |
1275 | } | |
1276 | } | |
1277 | ||
1278 | #[cfg(feature = "full")] | |
1279 | fn expr_no_struct(input: ParseStream) -> Result<Expr> { | |
1280 | ambiguous_expr(input, AllowStruct(false)) | |
1281 | } | |
1282 | ||
1283 | #[cfg(feature = "full")] | |
1284 | fn parse_expr( | |
1285 | input: ParseStream, | |
1286 | mut lhs: Expr, | |
1287 | allow_struct: AllowStruct, | |
1288 | base: Precedence, | |
1289 | ) -> Result<Expr> { | |
1290 | loop { | |
1291 | if input | |
1292 | .fork() | |
1293 | .parse::<BinOp>() | |
1294 | .ok() | |
1295 | .map_or(false, |op| Precedence::of(&op) >= base) | |
1296 | { | |
1297 | let op: BinOp = input.parse()?; | |
1298 | let precedence = Precedence::of(&op); | |
1299 | let mut rhs = unary_expr(input, allow_struct)?; | |
1300 | loop { | |
1301 | let next = peek_precedence(input); | |
1302 | if next > precedence || next == precedence && precedence == Precedence::Assign { | |
1303 | rhs = parse_expr(input, rhs, allow_struct, next)?; | |
1304 | } else { | |
1305 | break; | |
1306 | } | |
1307 | } | |
1308 | lhs = if precedence == Precedence::Assign { | |
1309 | Expr::AssignOp(ExprAssignOp { | |
1310 | attrs: Vec::new(), | |
1311 | left: Box::new(lhs), | |
1312 | op, | |
1313 | right: Box::new(rhs), | |
1314 | }) | |
1315 | } else { | |
1316 | Expr::Binary(ExprBinary { | |
1317 | attrs: Vec::new(), | |
1318 | left: Box::new(lhs), | |
1319 | op, | |
1320 | right: Box::new(rhs), | |
1321 | }) | |
1322 | }; | |
1323 | } else if Precedence::Assign >= base | |
1324 | && input.peek(Token![=]) | |
1325 | && !input.peek(Token![==]) | |
1326 | && !input.peek(Token![=>]) | |
1327 | { | |
1328 | let eq_token: Token![=] = input.parse()?; | |
1329 | let mut rhs = unary_expr(input, allow_struct)?; | |
1330 | loop { | |
1331 | let next = peek_precedence(input); | |
1332 | if next >= Precedence::Assign { | |
1333 | rhs = parse_expr(input, rhs, allow_struct, next)?; | |
1334 | } else { | |
1335 | break; | |
1336 | } | |
1337 | } | |
1338 | lhs = Expr::Assign(ExprAssign { | |
1339 | attrs: Vec::new(), | |
1340 | left: Box::new(lhs), | |
1341 | eq_token, | |
1342 | right: Box::new(rhs), | |
1343 | }); | |
1344 | } else if Precedence::Range >= base && input.peek(Token![..]) { | |
1345 | let limits: RangeLimits = input.parse()?; | |
1346 | let rhs = if input.is_empty() | |
1347 | || input.peek(Token![,]) | |
1348 | || input.peek(Token![;]) | |
1349 | || !allow_struct.0 && input.peek(token::Brace) | |
1350 | { | |
1351 | None | |
1352 | } else { | |
1353 | let mut rhs = unary_expr(input, allow_struct)?; | |
1354 | loop { | |
1355 | let next = peek_precedence(input); | |
1356 | if next > Precedence::Range { | |
1357 | rhs = parse_expr(input, rhs, allow_struct, next)?; | |
1358 | } else { | |
1359 | break; | |
1360 | } | |
1361 | } | |
1362 | Some(rhs) | |
1363 | }; | |
1364 | lhs = Expr::Range(ExprRange { | |
1365 | attrs: Vec::new(), | |
1366 | from: Some(Box::new(lhs)), | |
1367 | limits, | |
1368 | to: rhs.map(Box::new), | |
1369 | }); | |
1370 | } else if Precedence::Cast >= base && input.peek(Token![as]) { | |
1371 | let as_token: Token![as] = input.parse()?; | |
1372 | let ty = input.call(Type::without_plus)?; | |
1373 | lhs = Expr::Cast(ExprCast { | |
1374 | attrs: Vec::new(), | |
1375 | expr: Box::new(lhs), | |
1376 | as_token, | |
1377 | ty: Box::new(ty), | |
1378 | }); | |
1379 | } else if Precedence::Cast >= base && input.peek(Token![:]) && !input.peek(Token![::]) { | |
1380 | let colon_token: Token![:] = input.parse()?; | |
1381 | let ty = input.call(Type::without_plus)?; | |
1382 | lhs = Expr::Type(ExprType { | |
1383 | attrs: Vec::new(), | |
1384 | expr: Box::new(lhs), | |
1385 | colon_token, | |
1386 | ty: Box::new(ty), | |
1387 | }); | |
1388 | } else { | |
1389 | break; | |
1390 | } | |
1391 | } | |
1392 | Ok(lhs) | |
1393 | } | |
1394 | ||
1395 | #[cfg(not(feature = "full"))] | |
1396 | fn parse_expr( | |
1397 | input: ParseStream, | |
1398 | mut lhs: Expr, | |
1399 | allow_struct: AllowStruct, | |
1400 | base: Precedence, | |
1401 | ) -> Result<Expr> { | |
1402 | loop { | |
1403 | if input | |
1404 | .fork() | |
1405 | .parse::<BinOp>() | |
1406 | .ok() | |
1407 | .map_or(false, |op| Precedence::of(&op) >= base) | |
1408 | { | |
1409 | let op: BinOp = input.parse()?; | |
1410 | let precedence = Precedence::of(&op); | |
1411 | let mut rhs = unary_expr(input, allow_struct)?; | |
1412 | loop { | |
1413 | let next = peek_precedence(input); | |
1414 | if next > precedence || next == precedence && precedence == Precedence::Assign { | |
1415 | rhs = parse_expr(input, rhs, allow_struct, next)?; | |
1416 | } else { | |
1417 | break; | |
1418 | } | |
1419 | } | |
1420 | lhs = Expr::Binary(ExprBinary { | |
1421 | attrs: Vec::new(), | |
1422 | left: Box::new(lhs), | |
1423 | op, | |
1424 | right: Box::new(rhs), | |
1425 | }); | |
1426 | } else if Precedence::Cast >= base && input.peek(Token![as]) { | |
1427 | let as_token: Token![as] = input.parse()?; | |
1428 | let ty = input.call(Type::without_plus)?; | |
1429 | lhs = Expr::Cast(ExprCast { | |
1430 | attrs: Vec::new(), | |
1431 | expr: Box::new(lhs), | |
1432 | as_token, | |
1433 | ty: Box::new(ty), | |
1434 | }); | |
1435 | } else { | |
1436 | break; | |
1437 | } | |
1438 | } | |
1439 | Ok(lhs) | |
1440 | } | |
1441 | ||
1442 | fn peek_precedence(input: ParseStream) -> Precedence { | |
1443 | if let Ok(op) = input.fork().parse() { | |
1444 | Precedence::of(&op) | |
1445 | } else if input.peek(Token![=]) && !input.peek(Token![=>]) { | |
1446 | Precedence::Assign | |
1447 | } else if input.peek(Token![..]) { | |
1448 | Precedence::Range | |
1449 | } else if input.peek(Token![as]) || input.peek(Token![:]) && !input.peek(Token![::]) { | |
1450 | Precedence::Cast | |
1451 | } else { | |
1452 | Precedence::Any | |
1453 | } | |
1454 | } | |
1455 | ||
1456 | // Parse an arbitrary expression. | |
1457 | fn ambiguous_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1458 | let lhs = unary_expr(input, allow_struct)?; | |
1459 | parse_expr(input, lhs, allow_struct, Precedence::Any) | |
1460 | } | |
1461 | ||
1462 | // <UnOp> <trailer> | |
1463 | // & <trailer> | |
1464 | // &mut <trailer> | |
1465 | // box <trailer> | |
1466 | #[cfg(feature = "full")] | |
1467 | fn unary_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1468 | // TODO: optimize using advance_to | |
1469 | let ahead = input.fork(); | |
1470 | ahead.call(Attribute::parse_outer)?; | |
1471 | if ahead.peek(Token![&]) | |
1472 | || ahead.peek(Token![box]) | |
1473 | || ahead.peek(Token![*]) | |
1474 | || ahead.peek(Token![!]) | |
1475 | || ahead.peek(Token![-]) | |
1476 | { | |
1477 | let attrs = input.call(Attribute::parse_outer)?; | |
1478 | if input.peek(Token![&]) { | |
1479 | Ok(Expr::Reference(ExprReference { | |
1480 | attrs, | |
1481 | and_token: input.parse()?, | |
1482 | raw: Reserved::default(), | |
1483 | mutability: input.parse()?, | |
1484 | expr: Box::new(unary_expr(input, allow_struct)?), | |
1485 | })) | |
1486 | } else if input.peek(Token![box]) { | |
1487 | Ok(Expr::Box(ExprBox { | |
1488 | attrs, | |
1489 | box_token: input.parse()?, | |
1490 | expr: Box::new(unary_expr(input, allow_struct)?), | |
1491 | })) | |
1492 | } else { | |
1493 | Ok(Expr::Unary(ExprUnary { | |
1494 | attrs, | |
1495 | op: input.parse()?, | |
1496 | expr: Box::new(unary_expr(input, allow_struct)?), | |
1497 | })) | |
1498 | } | |
1499 | } else { | |
1500 | trailer_expr(input, allow_struct) | |
1501 | } | |
1502 | } | |
1503 | ||
1504 | #[cfg(not(feature = "full"))] | |
1505 | fn unary_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1506 | // TODO: optimize using advance_to | |
1507 | let ahead = input.fork(); | |
1508 | ahead.call(Attribute::parse_outer)?; | |
1509 | if ahead.peek(Token![*]) || ahead.peek(Token![!]) || ahead.peek(Token![-]) { | |
1510 | Ok(Expr::Unary(ExprUnary { | |
1511 | attrs: input.call(Attribute::parse_outer)?, | |
1512 | op: input.parse()?, | |
1513 | expr: Box::new(unary_expr(input, allow_struct)?), | |
1514 | })) | |
1515 | } else { | |
1516 | trailer_expr(input, allow_struct) | |
1517 | } | |
1518 | } | |
1519 | ||
1520 | // <atom> (..<args>) ... | |
1521 | // <atom> . <ident> (..<args>) ... | |
1522 | // <atom> . <ident> ... | |
1523 | // <atom> . <lit> ... | |
1524 | // <atom> [ <expr> ] ... | |
1525 | // <atom> ? ... | |
1526 | #[cfg(feature = "full")] | |
1527 | fn trailer_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1528 | if input.peek(token::Group) { | |
1529 | return input.call(expr_group).map(Expr::Group); | |
1530 | } | |
1531 | ||
1532 | let outer_attrs = input.call(Attribute::parse_outer)?; | |
1533 | ||
1534 | let atom = atom_expr(input, allow_struct)?; | |
1535 | let mut e = trailer_helper(input, atom)?; | |
1536 | ||
1537 | let inner_attrs = e.replace_attrs(Vec::new()); | |
1538 | let attrs = private::attrs(outer_attrs, inner_attrs); | |
1539 | e.replace_attrs(attrs); | |
1540 | Ok(e) | |
1541 | } | |
1542 | ||
1543 | #[cfg(feature = "full")] | |
1544 | fn trailer_helper(input: ParseStream, mut e: Expr) -> Result<Expr> { | |
1545 | loop { | |
1546 | if input.peek(token::Paren) { | |
1547 | let content; | |
1548 | e = Expr::Call(ExprCall { | |
1549 | attrs: Vec::new(), | |
1550 | func: Box::new(e), | |
1551 | paren_token: parenthesized!(content in input), | |
1552 | args: content.parse_terminated(Expr::parse)?, | |
1553 | }); | |
1554 | } else if input.peek(Token![.]) && !input.peek(Token![..]) { | |
1555 | let dot_token: Token![.] = input.parse()?; | |
1556 | ||
1557 | if input.peek(token::Await) { | |
1558 | e = Expr::Await(ExprAwait { | |
1559 | attrs: Vec::new(), | |
1560 | base: Box::new(e), | |
1561 | dot_token, | |
1562 | await_token: input.parse()?, | |
1563 | }); | |
1564 | continue; | |
1565 | } | |
1566 | ||
1567 | let member: Member = input.parse()?; | |
1568 | let turbofish = if member.is_named() && input.peek(Token![::]) { | |
1569 | Some(MethodTurbofish { | |
1570 | colon2_token: input.parse()?, | |
1571 | lt_token: input.parse()?, | |
1572 | args: { | |
1573 | let mut args = Punctuated::new(); | |
1574 | loop { | |
1575 | if input.peek(Token![>]) { | |
1576 | break; | |
1577 | } | |
1578 | let value = input.call(generic_method_argument)?; | |
1579 | args.push_value(value); | |
1580 | if input.peek(Token![>]) { | |
1581 | break; | |
1582 | } | |
1583 | let punct = input.parse()?; | |
1584 | args.push_punct(punct); | |
1585 | } | |
1586 | args | |
1587 | }, | |
1588 | gt_token: input.parse()?, | |
1589 | }) | |
1590 | } else { | |
1591 | None | |
1592 | }; | |
1593 | ||
1594 | if turbofish.is_some() || input.peek(token::Paren) { | |
1595 | if let Member::Named(method) = member { | |
1596 | let content; | |
1597 | e = Expr::MethodCall(ExprMethodCall { | |
1598 | attrs: Vec::new(), | |
1599 | receiver: Box::new(e), | |
1600 | dot_token, | |
1601 | method, | |
1602 | turbofish, | |
1603 | paren_token: parenthesized!(content in input), | |
1604 | args: content.parse_terminated(Expr::parse)?, | |
1605 | }); | |
1606 | continue; | |
1607 | } | |
1608 | } | |
1609 | ||
1610 | e = Expr::Field(ExprField { | |
1611 | attrs: Vec::new(), | |
1612 | base: Box::new(e), | |
1613 | dot_token, | |
1614 | member, | |
1615 | }); | |
1616 | } else if input.peek(token::Bracket) { | |
1617 | let content; | |
1618 | e = Expr::Index(ExprIndex { | |
1619 | attrs: Vec::new(), | |
1620 | expr: Box::new(e), | |
1621 | bracket_token: bracketed!(content in input), | |
1622 | index: content.parse()?, | |
1623 | }); | |
1624 | } else if input.peek(Token![?]) { | |
1625 | e = Expr::Try(ExprTry { | |
1626 | attrs: Vec::new(), | |
1627 | expr: Box::new(e), | |
1628 | question_token: input.parse()?, | |
1629 | }); | |
1630 | } else { | |
1631 | break; | |
1632 | } | |
1633 | } | |
1634 | Ok(e) | |
1635 | } | |
1636 | ||
1637 | #[cfg(not(feature = "full"))] | |
1638 | fn trailer_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1639 | let mut e = atom_expr(input, allow_struct)?; | |
1640 | ||
1641 | loop { | |
1642 | if input.peek(token::Paren) { | |
1643 | let content; | |
1644 | e = Expr::Call(ExprCall { | |
1645 | attrs: Vec::new(), | |
1646 | func: Box::new(e), | |
1647 | paren_token: parenthesized!(content in input), | |
1648 | args: content.parse_terminated(Expr::parse)?, | |
1649 | }); | |
1650 | } else if input.peek(Token![.]) && !input.peek(Token![..]) && !input.peek2(token::Await) | |
1651 | { | |
1652 | e = Expr::Field(ExprField { | |
1653 | attrs: Vec::new(), | |
1654 | base: Box::new(e), | |
1655 | dot_token: input.parse()?, | |
1656 | member: input.parse()?, | |
1657 | }); | |
1658 | } else if input.peek(token::Bracket) { | |
1659 | let content; | |
1660 | e = Expr::Index(ExprIndex { | |
1661 | attrs: Vec::new(), | |
1662 | expr: Box::new(e), | |
1663 | bracket_token: bracketed!(content in input), | |
1664 | index: content.parse()?, | |
1665 | }); | |
1666 | } else { | |
1667 | break; | |
1668 | } | |
1669 | } | |
1670 | ||
1671 | Ok(e) | |
1672 | } | |
1673 | ||
1674 | // Parse all atomic expressions which don't have to worry about precedence | |
1675 | // interactions, as they are fully contained. | |
1676 | #[cfg(feature = "full")] | |
1677 | fn atom_expr(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1678 | if input.peek(token::Group) { | |
1679 | input.call(expr_group).map(Expr::Group) | |
1680 | } else if input.peek(Lit) { | |
1681 | input.parse().map(Expr::Lit) | |
1682 | } else if input.peek(Token![async]) | |
1683 | && (input.peek2(token::Brace) || input.peek2(Token![move]) && input.peek3(token::Brace)) | |
1684 | { | |
1685 | input.call(expr_async).map(Expr::Async) | |
1686 | } else if input.peek(Token![try]) && input.peek2(token::Brace) { | |
1687 | input.call(expr_try_block).map(Expr::TryBlock) | |
1688 | } else if input.peek(Token![|]) | |
1689 | || input.peek(Token![async]) && (input.peek2(Token![|]) || input.peek2(Token![move])) | |
1690 | || input.peek(Token![static]) | |
1691 | || input.peek(Token![move]) | |
1692 | { | |
1693 | expr_closure(input, allow_struct).map(Expr::Closure) | |
1694 | } else if input.peek(Ident) | |
1695 | || input.peek(Token![::]) | |
1696 | || input.peek(Token![<]) | |
1697 | || input.peek(Token![self]) | |
1698 | || input.peek(Token![Self]) | |
1699 | || input.peek(Token![super]) | |
1700 | || input.peek(Token![extern]) | |
1701 | || input.peek(Token![crate]) | |
1702 | { | |
1703 | path_or_macro_or_struct(input, allow_struct) | |
1704 | } else if input.peek(token::Paren) { | |
1705 | paren_or_tuple(input) | |
1706 | } else if input.peek(Token![break]) { | |
1707 | expr_break(input, allow_struct).map(Expr::Break) | |
1708 | } else if input.peek(Token![continue]) { | |
1709 | input.call(expr_continue).map(Expr::Continue) | |
1710 | } else if input.peek(Token![return]) { | |
1711 | expr_ret(input, allow_struct).map(Expr::Return) | |
1712 | } else if input.peek(token::Bracket) { | |
1713 | array_or_repeat(input) | |
1714 | } else if input.peek(Token![let]) { | |
1715 | input.call(expr_let).map(Expr::Let) | |
1716 | } else if input.peek(Token![if]) { | |
1717 | input.parse().map(Expr::If) | |
1718 | } else if input.peek(Token![while]) { | |
1719 | input.parse().map(Expr::While) | |
1720 | } else if input.peek(Token![for]) { | |
1721 | input.parse().map(Expr::ForLoop) | |
1722 | } else if input.peek(Token![loop]) { | |
1723 | input.parse().map(Expr::Loop) | |
1724 | } else if input.peek(Token![match]) { | |
1725 | input.parse().map(Expr::Match) | |
1726 | } else if input.peek(Token![yield]) { | |
1727 | input.call(expr_yield).map(Expr::Yield) | |
1728 | } else if input.peek(Token![unsafe]) { | |
1729 | input.call(expr_unsafe).map(Expr::Unsafe) | |
1730 | } else if input.peek(token::Brace) { | |
1731 | input.call(expr_block).map(Expr::Block) | |
1732 | } else if input.peek(Token![..]) { | |
1733 | expr_range(input, allow_struct).map(Expr::Range) | |
1734 | } else if input.peek(Lifetime) { | |
1735 | let the_label: Label = input.parse()?; | |
1736 | let mut expr = if input.peek(Token![while]) { | |
1737 | Expr::While(input.parse()?) | |
1738 | } else if input.peek(Token![for]) { | |
1739 | Expr::ForLoop(input.parse()?) | |
1740 | } else if input.peek(Token![loop]) { | |
1741 | Expr::Loop(input.parse()?) | |
1742 | } else if input.peek(token::Brace) { | |
1743 | Expr::Block(input.call(expr_block)?) | |
1744 | } else { | |
1745 | return Err(input.error("expected loop or block expression")); | |
1746 | }; | |
1747 | match &mut expr { | |
1748 | Expr::While(ExprWhile { label, .. }) | |
1749 | | Expr::ForLoop(ExprForLoop { label, .. }) | |
1750 | | Expr::Loop(ExprLoop { label, .. }) | |
1751 | | Expr::Block(ExprBlock { label, .. }) => *label = Some(the_label), | |
1752 | _ => unreachable!(), | |
1753 | } | |
1754 | Ok(expr) | |
1755 | } else { | |
1756 | Err(input.error("expected expression")) | |
1757 | } | |
1758 | } | |
1759 | ||
1760 | #[cfg(not(feature = "full"))] | |
1761 | fn atom_expr(input: ParseStream, _allow_struct: AllowStruct) -> Result<Expr> { | |
1762 | if input.peek(Lit) { | |
1763 | input.parse().map(Expr::Lit) | |
1764 | } else if input.peek(token::Paren) { | |
1765 | input.call(expr_paren).map(Expr::Paren) | |
1766 | } else if input.peek(Ident) | |
1767 | || input.peek(Token![::]) | |
1768 | || input.peek(Token![<]) | |
1769 | || input.peek(Token![self]) | |
1770 | || input.peek(Token![Self]) | |
1771 | || input.peek(Token![super]) | |
1772 | || input.peek(Token![extern]) | |
1773 | || input.peek(Token![crate]) | |
1774 | { | |
1775 | input.parse().map(Expr::Path) | |
1776 | } else { | |
1777 | Err(input.error("unsupported expression; enable syn's features=[\"full\"]")) | |
1778 | } | |
1779 | } | |
1780 | ||
1781 | #[cfg(feature = "full")] | |
1782 | fn path_or_macro_or_struct(input: ParseStream, allow_struct: AllowStruct) -> Result<Expr> { | |
1783 | let expr: ExprPath = input.parse()?; | |
1784 | if expr.qself.is_some() { | |
1785 | return Ok(Expr::Path(expr)); | |
1786 | } | |
1787 | ||
1788 | if input.peek(Token![!]) && !input.peek(Token![!=]) { | |
1789 | let mut contains_arguments = false; | |
1790 | for segment in &expr.path.segments { | |
1791 | match segment.arguments { | |
1792 | PathArguments::None => {} | |
1793 | PathArguments::AngleBracketed(_) | PathArguments::Parenthesized(_) => { | |
1794 | contains_arguments = true; | |
1795 | } | |
1796 | } | |
1797 | } | |
1798 | ||
1799 | if !contains_arguments { | |
1800 | let bang_token: Token![!] = input.parse()?; | |
1801 | let (delimiter, tokens) = mac::parse_delimiter(input)?; | |
1802 | return Ok(Expr::Macro(ExprMacro { | |
1803 | attrs: Vec::new(), | |
1804 | mac: Macro { | |
1805 | path: expr.path, | |
1806 | bang_token, | |
1807 | delimiter, | |
1808 | tokens, | |
1809 | }, | |
1810 | })); | |
1811 | } | |
1812 | } | |
1813 | ||
1814 | if allow_struct.0 && input.peek(token::Brace) { | |
1815 | let outer_attrs = Vec::new(); | |
1816 | expr_struct_helper(input, outer_attrs, expr.path).map(Expr::Struct) | |
1817 | } else { | |
1818 | Ok(Expr::Path(expr)) | |
1819 | } | |
1820 | } | |
1821 | ||
1822 | #[cfg(feature = "full")] | |
1823 | fn paren_or_tuple(input: ParseStream) -> Result<Expr> { | |
1824 | let content; | |
1825 | let paren_token = parenthesized!(content in input); | |
1826 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
1827 | if content.is_empty() { | |
1828 | return Ok(Expr::Tuple(ExprTuple { | |
1829 | attrs: inner_attrs, | |
1830 | paren_token, | |
1831 | elems: Punctuated::new(), | |
1832 | })); | |
1833 | } | |
1834 | ||
1835 | let first: Expr = content.parse()?; | |
1836 | if content.is_empty() { | |
1837 | return Ok(Expr::Paren(ExprParen { | |
1838 | attrs: inner_attrs, | |
1839 | paren_token, | |
1840 | expr: Box::new(first), | |
1841 | })); | |
1842 | } | |
1843 | ||
1844 | let mut elems = Punctuated::new(); | |
1845 | elems.push_value(first); | |
1846 | while !content.is_empty() { | |
1847 | let punct = content.parse()?; | |
1848 | elems.push_punct(punct); | |
1849 | if content.is_empty() { | |
1850 | break; | |
1851 | } | |
1852 | let value = content.parse()?; | |
1853 | elems.push_value(value); | |
1854 | } | |
1855 | Ok(Expr::Tuple(ExprTuple { | |
1856 | attrs: inner_attrs, | |
1857 | paren_token, | |
1858 | elems, | |
1859 | })) | |
1860 | } | |
1861 | ||
1862 | #[cfg(feature = "full")] | |
1863 | fn array_or_repeat(input: ParseStream) -> Result<Expr> { | |
1864 | let content; | |
1865 | let bracket_token = bracketed!(content in input); | |
1866 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
1867 | if content.is_empty() { | |
1868 | return Ok(Expr::Array(ExprArray { | |
1869 | attrs: inner_attrs, | |
1870 | bracket_token, | |
1871 | elems: Punctuated::new(), | |
1872 | })); | |
1873 | } | |
1874 | ||
1875 | let first: Expr = content.parse()?; | |
1876 | if content.is_empty() || content.peek(Token![,]) { | |
1877 | let mut elems = Punctuated::new(); | |
1878 | elems.push_value(first); | |
1879 | while !content.is_empty() { | |
1880 | let punct = content.parse()?; | |
1881 | elems.push_punct(punct); | |
1882 | if content.is_empty() { | |
1883 | break; | |
1884 | } | |
1885 | let value = content.parse()?; | |
1886 | elems.push_value(value); | |
1887 | } | |
1888 | Ok(Expr::Array(ExprArray { | |
1889 | attrs: inner_attrs, | |
1890 | bracket_token, | |
1891 | elems, | |
1892 | })) | |
1893 | } else if content.peek(Token![;]) { | |
1894 | let semi_token: Token![;] = content.parse()?; | |
1895 | let len: Expr = content.parse()?; | |
1896 | Ok(Expr::Repeat(ExprRepeat { | |
1897 | attrs: inner_attrs, | |
1898 | bracket_token, | |
1899 | expr: Box::new(first), | |
1900 | semi_token, | |
1901 | len: Box::new(len), | |
1902 | })) | |
1903 | } else { | |
1904 | Err(content.error("expected `,` or `;`")) | |
1905 | } | |
1906 | } | |
1907 | ||
1908 | #[cfg(feature = "full")] | |
1909 | pub(crate) fn expr_early(input: ParseStream) -> Result<Expr> { | |
1910 | let mut attrs = input.call(Attribute::parse_outer)?; | |
1911 | let mut expr = if input.peek(Token![if]) { | |
1912 | Expr::If(input.parse()?) | |
1913 | } else if input.peek(Token![while]) { | |
1914 | Expr::While(input.parse()?) | |
1915 | } else if input.peek(Token![for]) { | |
1916 | Expr::ForLoop(input.parse()?) | |
1917 | } else if input.peek(Token![loop]) { | |
1918 | Expr::Loop(input.parse()?) | |
1919 | } else if input.peek(Token![match]) { | |
1920 | Expr::Match(input.parse()?) | |
1921 | } else if input.peek(Token![try]) && input.peek2(token::Brace) { | |
1922 | Expr::TryBlock(input.call(expr_try_block)?) | |
1923 | } else if input.peek(Token![unsafe]) { | |
1924 | Expr::Unsafe(input.call(expr_unsafe)?) | |
1925 | } else if input.peek(token::Brace) { | |
1926 | Expr::Block(input.call(expr_block)?) | |
1927 | } else { | |
1928 | let allow_struct = AllowStruct(true); | |
1929 | let mut expr = unary_expr(input, allow_struct)?; | |
1930 | ||
1931 | attrs.extend(expr.replace_attrs(Vec::new())); | |
1932 | expr.replace_attrs(attrs); | |
1933 | ||
1934 | return parse_expr(input, expr, allow_struct, Precedence::Any); | |
1935 | }; | |
1936 | ||
1937 | if input.peek(Token![.]) || input.peek(Token![?]) { | |
1938 | expr = trailer_helper(input, expr)?; | |
1939 | ||
1940 | attrs.extend(expr.replace_attrs(Vec::new())); | |
1941 | expr.replace_attrs(attrs); | |
1942 | ||
1943 | let allow_struct = AllowStruct(true); | |
1944 | return parse_expr(input, expr, allow_struct, Precedence::Any); | |
1945 | } | |
1946 | ||
1947 | attrs.extend(expr.replace_attrs(Vec::new())); | |
1948 | expr.replace_attrs(attrs); | |
1949 | Ok(expr) | |
1950 | } | |
1951 | ||
1952 | impl Parse for ExprLit { | |
1953 | fn parse(input: ParseStream) -> Result<Self> { | |
1954 | Ok(ExprLit { | |
1955 | attrs: Vec::new(), | |
1956 | lit: input.parse()?, | |
1957 | }) | |
1958 | } | |
1959 | } | |
1960 | ||
1961 | #[cfg(feature = "full")] | |
1962 | fn expr_group(input: ParseStream) -> Result<ExprGroup> { | |
1963 | let group = crate::group::parse_group(input)?; | |
1964 | Ok(ExprGroup { | |
1965 | attrs: Vec::new(), | |
1966 | group_token: group.token, | |
1967 | expr: group.content.parse()?, | |
1968 | }) | |
1969 | } | |
1970 | ||
1971 | #[cfg(not(feature = "full"))] | |
1972 | fn expr_paren(input: ParseStream) -> Result<ExprParen> { | |
1973 | let content; | |
1974 | Ok(ExprParen { | |
1975 | attrs: Vec::new(), | |
1976 | paren_token: parenthesized!(content in input), | |
1977 | expr: content.parse()?, | |
1978 | }) | |
1979 | } | |
1980 | ||
1981 | #[cfg(feature = "full")] | |
1982 | fn generic_method_argument(input: ParseStream) -> Result<GenericMethodArgument> { | |
1983 | // TODO parse const generics as well | |
1984 | input.parse().map(GenericMethodArgument::Type) | |
1985 | } | |
1986 | ||
1987 | #[cfg(feature = "full")] | |
1988 | fn expr_let(input: ParseStream) -> Result<ExprLet> { | |
1989 | Ok(ExprLet { | |
1990 | attrs: Vec::new(), | |
1991 | let_token: input.parse()?, | |
1992 | pat: { | |
1993 | let leading_vert: Option<Token![|]> = input.parse()?; | |
1994 | let pat: Pat = input.parse()?; | |
1995 | if leading_vert.is_some() | |
1996 | || input.peek(Token![|]) && !input.peek(Token![||]) && !input.peek(Token![|=]) | |
1997 | { | |
1998 | let mut cases = Punctuated::new(); | |
1999 | cases.push_value(pat); | |
2000 | while input.peek(Token![|]) | |
2001 | && !input.peek(Token![||]) | |
2002 | && !input.peek(Token![|=]) | |
2003 | { | |
2004 | let punct = input.parse()?; | |
2005 | cases.push_punct(punct); | |
2006 | let pat: Pat = input.parse()?; | |
2007 | cases.push_value(pat); | |
2008 | } | |
2009 | Pat::Or(PatOr { | |
2010 | attrs: Vec::new(), | |
2011 | leading_vert, | |
2012 | cases, | |
2013 | }) | |
2014 | } else { | |
2015 | pat | |
2016 | } | |
2017 | }, | |
2018 | eq_token: input.parse()?, | |
2019 | expr: Box::new(input.call(expr_no_struct)?), | |
2020 | }) | |
2021 | } | |
2022 | ||
2023 | #[cfg(feature = "full")] | |
2024 | impl Parse for ExprIf { | |
2025 | fn parse(input: ParseStream) -> Result<Self> { | |
2026 | Ok(ExprIf { | |
2027 | attrs: Vec::new(), | |
2028 | if_token: input.parse()?, | |
2029 | cond: Box::new(input.call(expr_no_struct)?), | |
2030 | then_branch: input.parse()?, | |
2031 | else_branch: { | |
2032 | if input.peek(Token![else]) { | |
2033 | Some(input.call(else_block)?) | |
2034 | } else { | |
2035 | None | |
2036 | } | |
2037 | }, | |
2038 | }) | |
2039 | } | |
2040 | } | |
2041 | ||
2042 | #[cfg(feature = "full")] | |
2043 | fn else_block(input: ParseStream) -> Result<(Token![else], Box<Expr>)> { | |
2044 | let else_token: Token![else] = input.parse()?; | |
2045 | ||
2046 | let lookahead = input.lookahead1(); | |
2047 | let else_branch = if input.peek(Token![if]) { | |
2048 | input.parse().map(Expr::If)? | |
2049 | } else if input.peek(token::Brace) { | |
2050 | Expr::Block(ExprBlock { | |
2051 | attrs: Vec::new(), | |
2052 | label: None, | |
2053 | block: input.parse()?, | |
2054 | }) | |
2055 | } else { | |
2056 | return Err(lookahead.error()); | |
2057 | }; | |
2058 | ||
2059 | Ok((else_token, Box::new(else_branch))) | |
2060 | } | |
2061 | ||
2062 | #[cfg(feature = "full")] | |
2063 | impl Parse for ExprForLoop { | |
2064 | fn parse(input: ParseStream) -> Result<Self> { | |
2065 | let label: Option<Label> = input.parse()?; | |
2066 | let for_token: Token![for] = input.parse()?; | |
2067 | ||
2068 | let leading_vert: Option<Token![|]> = input.parse()?; | |
2069 | let mut pat: Pat = input.parse()?; | |
2070 | if leading_vert.is_some() || input.peek(Token![|]) { | |
2071 | let mut cases = Punctuated::new(); | |
2072 | cases.push_value(pat); | |
2073 | while input.peek(Token![|]) { | |
2074 | let punct = input.parse()?; | |
2075 | cases.push_punct(punct); | |
2076 | let pat: Pat = input.parse()?; | |
2077 | cases.push_value(pat); | |
2078 | } | |
2079 | pat = Pat::Or(PatOr { | |
2080 | attrs: Vec::new(), | |
2081 | leading_vert, | |
2082 | cases, | |
2083 | }); | |
2084 | } | |
2085 | ||
2086 | let in_token: Token![in] = input.parse()?; | |
2087 | let expr: Expr = input.call(expr_no_struct)?; | |
2088 | ||
2089 | let content; | |
2090 | let brace_token = braced!(content in input); | |
2091 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2092 | let stmts = content.call(Block::parse_within)?; | |
2093 | ||
2094 | Ok(ExprForLoop { | |
2095 | attrs: inner_attrs, | |
2096 | label, | |
2097 | for_token, | |
2098 | pat, | |
2099 | in_token, | |
2100 | expr: Box::new(expr), | |
2101 | body: Block { brace_token, stmts }, | |
2102 | }) | |
2103 | } | |
2104 | } | |
2105 | ||
2106 | #[cfg(feature = "full")] | |
2107 | impl Parse for ExprLoop { | |
2108 | fn parse(input: ParseStream) -> Result<Self> { | |
2109 | let label: Option<Label> = input.parse()?; | |
2110 | let loop_token: Token![loop] = input.parse()?; | |
2111 | ||
2112 | let content; | |
2113 | let brace_token = braced!(content in input); | |
2114 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2115 | let stmts = content.call(Block::parse_within)?; | |
2116 | ||
2117 | Ok(ExprLoop { | |
2118 | attrs: inner_attrs, | |
2119 | label, | |
2120 | loop_token, | |
2121 | body: Block { brace_token, stmts }, | |
2122 | }) | |
2123 | } | |
2124 | } | |
2125 | ||
2126 | #[cfg(feature = "full")] | |
2127 | impl Parse for ExprMatch { | |
2128 | fn parse(input: ParseStream) -> Result<Self> { | |
2129 | let match_token: Token![match] = input.parse()?; | |
2130 | let expr = expr_no_struct(input)?; | |
2131 | ||
2132 | let content; | |
2133 | let brace_token = braced!(content in input); | |
2134 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2135 | ||
2136 | let mut arms = Vec::new(); | |
2137 | while !content.is_empty() { | |
2138 | arms.push(content.call(Arm::parse)?); | |
2139 | } | |
2140 | ||
2141 | Ok(ExprMatch { | |
2142 | attrs: inner_attrs, | |
2143 | match_token, | |
2144 | expr: Box::new(expr), | |
2145 | brace_token, | |
2146 | arms, | |
2147 | }) | |
2148 | } | |
2149 | } | |
2150 | ||
2151 | macro_rules! impl_by_parsing_expr { | |
2152 | ( | |
2153 | $( | |
2154 | $expr_type:ty, $variant:ident, $msg:expr, | |
2155 | )* | |
2156 | ) => { | |
2157 | $( | |
2158 | #[cfg(all(feature = "full", feature = "printing"))] | |
2159 | impl Parse for $expr_type { | |
2160 | fn parse(input: ParseStream) -> Result<Self> { | |
2161 | let mut expr: Expr = input.parse()?; | |
2162 | loop { | |
2163 | match expr { | |
2164 | Expr::$variant(inner) => return Ok(inner), | |
2165 | Expr::Group(next) => expr = *next.expr, | |
2166 | _ => return Err(Error::new_spanned(expr, $msg)), | |
2167 | } | |
2168 | } | |
2169 | } | |
2170 | } | |
2171 | )* | |
2172 | }; | |
2173 | } | |
2174 | ||
2175 | impl_by_parsing_expr! { | |
2176 | ExprBox, Box, "expected box expression", | |
2177 | ExprArray, Array, "expected slice literal expression", | |
2178 | ExprCall, Call, "expected function call expression", | |
2179 | ExprMethodCall, MethodCall, "expected method call expression", | |
2180 | ExprTuple, Tuple, "expected tuple expression", | |
2181 | ExprBinary, Binary, "expected binary operation", | |
2182 | ExprUnary, Unary, "expected unary operation", | |
2183 | ExprCast, Cast, "expected cast expression", | |
2184 | ExprType, Type, "expected type ascription expression", | |
2185 | ExprLet, Let, "expected let guard", | |
2186 | ExprClosure, Closure, "expected closure expression", | |
2187 | ExprUnsafe, Unsafe, "expected unsafe block", | |
2188 | ExprBlock, Block, "expected blocked scope", | |
2189 | ExprAssign, Assign, "expected assignment expression", | |
2190 | ExprAssignOp, AssignOp, "expected compound assignment expression", | |
2191 | ExprField, Field, "expected struct field access", | |
2192 | ExprIndex, Index, "expected indexing expression", | |
2193 | ExprRange, Range, "expected range expression", | |
2194 | ExprReference, Reference, "expected referencing operation", | |
2195 | ExprBreak, Break, "expected break expression", | |
2196 | ExprContinue, Continue, "expected continue expression", | |
2197 | ExprReturn, Return, "expected return expression", | |
2198 | ExprMacro, Macro, "expected macro invocation expression", | |
2199 | ExprStruct, Struct, "expected struct literal expression", | |
2200 | ExprRepeat, Repeat, "expected array literal constructed from one repeated element", | |
2201 | ExprParen, Paren, "expected parenthesized expression", | |
2202 | ExprTry, Try, "expected try expression", | |
2203 | ExprAsync, Async, "expected async block", | |
2204 | ExprTryBlock, TryBlock, "expected try block", | |
2205 | ExprYield, Yield, "expected yield expression", | |
2206 | } | |
2207 | ||
2208 | #[cfg(feature = "full")] | |
2209 | fn expr_try_block(input: ParseStream) -> Result<ExprTryBlock> { | |
2210 | Ok(ExprTryBlock { | |
2211 | attrs: Vec::new(), | |
2212 | try_token: input.parse()?, | |
2213 | block: input.parse()?, | |
2214 | }) | |
2215 | } | |
2216 | ||
2217 | #[cfg(feature = "full")] | |
2218 | fn expr_yield(input: ParseStream) -> Result<ExprYield> { | |
2219 | Ok(ExprYield { | |
2220 | attrs: Vec::new(), | |
2221 | yield_token: input.parse()?, | |
2222 | expr: { | |
2223 | if !input.is_empty() && !input.peek(Token![,]) && !input.peek(Token![;]) { | |
2224 | Some(input.parse()?) | |
2225 | } else { | |
2226 | None | |
2227 | } | |
2228 | }, | |
2229 | }) | |
2230 | } | |
2231 | ||
2232 | #[cfg(feature = "full")] | |
2233 | fn expr_closure(input: ParseStream, allow_struct: AllowStruct) -> Result<ExprClosure> { | |
2234 | let asyncness: Option<Token![async]> = input.parse()?; | |
2235 | let movability: Option<Token![static]> = if asyncness.is_none() { | |
2236 | input.parse()? | |
2237 | } else { | |
2238 | None | |
2239 | }; | |
2240 | let capture: Option<Token![move]> = input.parse()?; | |
2241 | let or1_token: Token![|] = input.parse()?; | |
2242 | ||
2243 | let mut inputs = Punctuated::new(); | |
2244 | loop { | |
2245 | if input.peek(Token![|]) { | |
2246 | break; | |
2247 | } | |
2248 | let value = closure_arg(input)?; | |
2249 | inputs.push_value(value); | |
2250 | if input.peek(Token![|]) { | |
2251 | break; | |
2252 | } | |
2253 | let punct: Token![,] = input.parse()?; | |
2254 | inputs.push_punct(punct); | |
2255 | } | |
2256 | ||
2257 | let or2_token: Token![|] = input.parse()?; | |
2258 | ||
2259 | let (output, body) = if input.peek(Token![->]) { | |
2260 | let arrow_token: Token![->] = input.parse()?; | |
2261 | let ty: Type = input.parse()?; | |
2262 | let body: Block = input.parse()?; | |
2263 | let output = ReturnType::Type(arrow_token, Box::new(ty)); | |
2264 | let block = Expr::Block(ExprBlock { | |
2265 | attrs: Vec::new(), | |
2266 | label: None, | |
2267 | block: body, | |
2268 | }); | |
2269 | (output, block) | |
2270 | } else { | |
2271 | let body = ambiguous_expr(input, allow_struct)?; | |
2272 | (ReturnType::Default, body) | |
2273 | }; | |
2274 | ||
2275 | Ok(ExprClosure { | |
2276 | attrs: Vec::new(), | |
2277 | asyncness, | |
2278 | movability, | |
2279 | capture, | |
2280 | or1_token, | |
2281 | inputs, | |
2282 | or2_token, | |
2283 | output, | |
2284 | body: Box::new(body), | |
2285 | }) | |
2286 | } | |
2287 | ||
2288 | #[cfg(feature = "full")] | |
2289 | fn expr_async(input: ParseStream) -> Result<ExprAsync> { | |
2290 | Ok(ExprAsync { | |
2291 | attrs: Vec::new(), | |
2292 | async_token: input.parse()?, | |
2293 | capture: input.parse()?, | |
2294 | block: input.parse()?, | |
2295 | }) | |
2296 | } | |
2297 | ||
2298 | #[cfg(feature = "full")] | |
2299 | fn closure_arg(input: ParseStream) -> Result<Pat> { | |
2300 | let attrs = input.call(Attribute::parse_outer)?; | |
2301 | let mut pat: Pat = input.parse()?; | |
2302 | ||
2303 | if input.peek(Token![:]) { | |
2304 | Ok(Pat::Type(PatType { | |
2305 | attrs, | |
2306 | pat: Box::new(pat), | |
2307 | colon_token: input.parse()?, | |
2308 | ty: input.parse()?, | |
2309 | })) | |
2310 | } else { | |
2311 | match &mut pat { | |
2312 | Pat::Box(pat) => pat.attrs = attrs, | |
2313 | Pat::Ident(pat) => pat.attrs = attrs, | |
2314 | Pat::Lit(pat) => pat.attrs = attrs, | |
2315 | Pat::Macro(pat) => pat.attrs = attrs, | |
2316 | Pat::Or(pat) => pat.attrs = attrs, | |
2317 | Pat::Path(pat) => pat.attrs = attrs, | |
2318 | Pat::Range(pat) => pat.attrs = attrs, | |
2319 | Pat::Reference(pat) => pat.attrs = attrs, | |
2320 | Pat::Rest(pat) => pat.attrs = attrs, | |
2321 | Pat::Slice(pat) => pat.attrs = attrs, | |
2322 | Pat::Struct(pat) => pat.attrs = attrs, | |
2323 | Pat::Tuple(pat) => pat.attrs = attrs, | |
2324 | Pat::TupleStruct(pat) => pat.attrs = attrs, | |
2325 | Pat::Type(_) => unreachable!(), | |
2326 | Pat::Verbatim(_) => {} | |
2327 | Pat::Wild(pat) => pat.attrs = attrs, | |
2328 | Pat::__Nonexhaustive => unreachable!(), | |
2329 | } | |
2330 | Ok(pat) | |
2331 | } | |
2332 | } | |
2333 | ||
2334 | #[cfg(feature = "full")] | |
2335 | impl Parse for ExprWhile { | |
2336 | fn parse(input: ParseStream) -> Result<Self> { | |
2337 | let label: Option<Label> = input.parse()?; | |
2338 | let while_token: Token![while] = input.parse()?; | |
2339 | let cond = expr_no_struct(input)?; | |
2340 | ||
2341 | let content; | |
2342 | let brace_token = braced!(content in input); | |
2343 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2344 | let stmts = content.call(Block::parse_within)?; | |
2345 | ||
2346 | Ok(ExprWhile { | |
2347 | attrs: inner_attrs, | |
2348 | label, | |
2349 | while_token, | |
2350 | cond: Box::new(cond), | |
2351 | body: Block { brace_token, stmts }, | |
2352 | }) | |
2353 | } | |
2354 | } | |
2355 | ||
2356 | #[cfg(feature = "full")] | |
2357 | impl Parse for Label { | |
2358 | fn parse(input: ParseStream) -> Result<Self> { | |
2359 | Ok(Label { | |
2360 | name: input.parse()?, | |
2361 | colon_token: input.parse()?, | |
2362 | }) | |
2363 | } | |
2364 | } | |
2365 | ||
2366 | #[cfg(feature = "full")] | |
2367 | impl Parse for Option<Label> { | |
2368 | fn parse(input: ParseStream) -> Result<Self> { | |
2369 | if input.peek(Lifetime) { | |
2370 | input.parse().map(Some) | |
2371 | } else { | |
2372 | Ok(None) | |
2373 | } | |
2374 | } | |
2375 | } | |
2376 | ||
2377 | #[cfg(feature = "full")] | |
2378 | fn expr_continue(input: ParseStream) -> Result<ExprContinue> { | |
2379 | Ok(ExprContinue { | |
2380 | attrs: Vec::new(), | |
2381 | continue_token: input.parse()?, | |
2382 | label: input.parse()?, | |
2383 | }) | |
2384 | } | |
2385 | ||
2386 | #[cfg(feature = "full")] | |
2387 | fn expr_break(input: ParseStream, allow_struct: AllowStruct) -> Result<ExprBreak> { | |
2388 | Ok(ExprBreak { | |
2389 | attrs: Vec::new(), | |
2390 | break_token: input.parse()?, | |
2391 | label: input.parse()?, | |
2392 | expr: { | |
2393 | if input.is_empty() | |
2394 | || input.peek(Token![,]) | |
2395 | || input.peek(Token![;]) | |
2396 | || !allow_struct.0 && input.peek(token::Brace) | |
2397 | { | |
2398 | None | |
2399 | } else { | |
2400 | let expr = ambiguous_expr(input, allow_struct)?; | |
2401 | Some(Box::new(expr)) | |
2402 | } | |
2403 | }, | |
2404 | }) | |
2405 | } | |
2406 | ||
2407 | #[cfg(feature = "full")] | |
2408 | fn expr_ret(input: ParseStream, allow_struct: AllowStruct) -> Result<ExprReturn> { | |
2409 | Ok(ExprReturn { | |
2410 | attrs: Vec::new(), | |
2411 | return_token: input.parse()?, | |
2412 | expr: { | |
2413 | if input.is_empty() || input.peek(Token![,]) || input.peek(Token![;]) { | |
2414 | None | |
2415 | } else { | |
2416 | // NOTE: return is greedy and eats blocks after it even when in a | |
2417 | // position where structs are not allowed, such as in if statement | |
2418 | // conditions. For example: | |
2419 | // | |
2420 | // if return { println!("A") } {} // Prints "A" | |
2421 | let expr = ambiguous_expr(input, allow_struct)?; | |
2422 | Some(Box::new(expr)) | |
2423 | } | |
2424 | }, | |
2425 | }) | |
2426 | } | |
2427 | ||
2428 | #[cfg(feature = "full")] | |
2429 | impl Parse for FieldValue { | |
2430 | fn parse(input: ParseStream) -> Result<Self> { | |
2431 | let member: Member = input.parse()?; | |
2432 | let (colon_token, value) = if input.peek(Token![:]) || !member.is_named() { | |
2433 | let colon_token: Token![:] = input.parse()?; | |
2434 | let value: Expr = input.parse()?; | |
2435 | (Some(colon_token), value) | |
2436 | } else if let Member::Named(ident) = &member { | |
2437 | let value = Expr::Path(ExprPath { | |
2438 | attrs: Vec::new(), | |
2439 | qself: None, | |
2440 | path: Path::from(ident.clone()), | |
2441 | }); | |
2442 | (None, value) | |
2443 | } else { | |
2444 | unreachable!() | |
2445 | }; | |
2446 | ||
2447 | Ok(FieldValue { | |
2448 | attrs: Vec::new(), | |
2449 | member, | |
2450 | colon_token, | |
2451 | expr: value, | |
2452 | }) | |
2453 | } | |
2454 | } | |
2455 | ||
2456 | #[cfg(feature = "full")] | |
2457 | fn expr_struct_helper( | |
2458 | input: ParseStream, | |
2459 | outer_attrs: Vec<Attribute>, | |
2460 | path: Path, | |
2461 | ) -> Result<ExprStruct> { | |
2462 | let content; | |
2463 | let brace_token = braced!(content in input); | |
2464 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2465 | ||
2466 | let mut fields = Punctuated::new(); | |
2467 | loop { | |
2468 | let attrs = content.call(Attribute::parse_outer)?; | |
2469 | // TODO: optimize using advance_to | |
2470 | if content.fork().parse::<Member>().is_err() { | |
2471 | if attrs.is_empty() { | |
2472 | break; | |
2473 | } else { | |
2474 | return Err(content.error("expected struct field")); | |
2475 | } | |
2476 | } | |
2477 | ||
2478 | fields.push(FieldValue { | |
2479 | attrs, | |
2480 | ..content.parse()? | |
2481 | }); | |
2482 | ||
2483 | if !content.peek(Token![,]) { | |
2484 | break; | |
2485 | } | |
2486 | let punct: Token![,] = content.parse()?; | |
2487 | fields.push_punct(punct); | |
2488 | } | |
2489 | ||
2490 | let (dot2_token, rest) = if fields.empty_or_trailing() && content.peek(Token![..]) { | |
2491 | let dot2_token: Token![..] = content.parse()?; | |
2492 | let rest: Expr = content.parse()?; | |
2493 | (Some(dot2_token), Some(Box::new(rest))) | |
2494 | } else { | |
2495 | (None, None) | |
2496 | }; | |
2497 | ||
2498 | Ok(ExprStruct { | |
2499 | attrs: private::attrs(outer_attrs, inner_attrs), | |
2500 | brace_token, | |
2501 | path, | |
2502 | fields, | |
2503 | dot2_token, | |
2504 | rest, | |
2505 | }) | |
2506 | } | |
2507 | ||
2508 | #[cfg(feature = "full")] | |
2509 | fn expr_unsafe(input: ParseStream) -> Result<ExprUnsafe> { | |
2510 | let unsafe_token: Token![unsafe] = input.parse()?; | |
2511 | ||
2512 | let content; | |
2513 | let brace_token = braced!(content in input); | |
2514 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2515 | let stmts = content.call(Block::parse_within)?; | |
2516 | ||
2517 | Ok(ExprUnsafe { | |
2518 | attrs: inner_attrs, | |
2519 | unsafe_token, | |
2520 | block: Block { brace_token, stmts }, | |
2521 | }) | |
2522 | } | |
2523 | ||
2524 | #[cfg(feature = "full")] | |
2525 | pub fn expr_block(input: ParseStream) -> Result<ExprBlock> { | |
2526 | let label: Option<Label> = input.parse()?; | |
2527 | ||
2528 | let content; | |
2529 | let brace_token = braced!(content in input); | |
2530 | let inner_attrs = content.call(Attribute::parse_inner)?; | |
2531 | let stmts = content.call(Block::parse_within)?; | |
2532 | ||
2533 | Ok(ExprBlock { | |
2534 | attrs: inner_attrs, | |
2535 | label, | |
2536 | block: Block { brace_token, stmts }, | |
2537 | }) | |
2538 | } | |
2539 | ||
2540 | #[cfg(feature = "full")] | |
2541 | fn expr_range(input: ParseStream, allow_struct: AllowStruct) -> Result<ExprRange> { | |
2542 | Ok(ExprRange { | |
2543 | attrs: Vec::new(), | |
2544 | from: None, | |
2545 | limits: input.parse()?, | |
2546 | to: { | |
2547 | if input.is_empty() | |
2548 | || input.peek(Token![,]) | |
2549 | || input.peek(Token![;]) | |
2550 | || !allow_struct.0 && input.peek(token::Brace) | |
2551 | { | |
2552 | None | |
2553 | } else { | |
2554 | let to = ambiguous_expr(input, allow_struct)?; | |
2555 | Some(Box::new(to)) | |
2556 | } | |
2557 | }, | |
2558 | }) | |
2559 | } | |
2560 | ||
2561 | #[cfg(feature = "full")] | |
2562 | impl Parse for RangeLimits { | |
2563 | fn parse(input: ParseStream) -> Result<Self> { | |
2564 | let lookahead = input.lookahead1(); | |
2565 | if lookahead.peek(Token![..=]) { | |
2566 | input.parse().map(RangeLimits::Closed) | |
2567 | } else if lookahead.peek(Token![...]) { | |
2568 | let dot3: Token![...] = input.parse()?; | |
2569 | Ok(RangeLimits::Closed(Token![..=](dot3.spans))) | |
2570 | } else if lookahead.peek(Token![..]) { | |
2571 | input.parse().map(RangeLimits::HalfOpen) | |
2572 | } else { | |
2573 | Err(lookahead.error()) | |
2574 | } | |
2575 | } | |
2576 | } | |
2577 | ||
2578 | impl Parse for ExprPath { | |
2579 | fn parse(input: ParseStream) -> Result<Self> { | |
2580 | #[cfg(not(feature = "full"))] | |
2581 | let attrs = Vec::new(); | |
2582 | #[cfg(feature = "full")] | |
2583 | let attrs = input.call(Attribute::parse_outer)?; | |
2584 | ||
2585 | let (qself, path) = path::parsing::qpath(input, true)?; | |
2586 | ||
2587 | Ok(ExprPath { attrs, qself, path }) | |
2588 | } | |
2589 | } | |
2590 | ||
2591 | impl Parse for Member { | |
2592 | fn parse(input: ParseStream) -> Result<Self> { | |
2593 | if input.peek(Ident) { | |
2594 | input.parse().map(Member::Named) | |
2595 | } else if input.peek(LitInt) { | |
2596 | input.parse().map(Member::Unnamed) | |
2597 | } else { | |
2598 | Err(input.error("expected identifier or integer")) | |
2599 | } | |
2600 | } | |
2601 | } | |
2602 | ||
2603 | #[cfg(feature = "full")] | |
2604 | impl Parse for Arm { | |
2605 | fn parse(input: ParseStream) -> Result<Arm> { | |
2606 | let requires_comma; | |
2607 | Ok(Arm { | |
2608 | attrs: input.call(Attribute::parse_outer)?, | |
2609 | pat: { | |
2610 | let leading_vert: Option<Token![|]> = input.parse()?; | |
2611 | let pat: Pat = input.parse()?; | |
2612 | if leading_vert.is_some() || input.peek(Token![|]) { | |
2613 | let mut cases = Punctuated::new(); | |
2614 | cases.push_value(pat); | |
2615 | while input.peek(Token![|]) { | |
2616 | let punct = input.parse()?; | |
2617 | cases.push_punct(punct); | |
2618 | let pat: Pat = input.parse()?; | |
2619 | cases.push_value(pat); | |
2620 | } | |
2621 | Pat::Or(PatOr { | |
2622 | attrs: Vec::new(), | |
2623 | leading_vert, | |
2624 | cases, | |
2625 | }) | |
2626 | } else { | |
2627 | pat | |
2628 | } | |
2629 | }, | |
2630 | guard: { | |
2631 | if input.peek(Token![if]) { | |
2632 | let if_token: Token![if] = input.parse()?; | |
2633 | let guard: Expr = input.parse()?; | |
2634 | Some((if_token, Box::new(guard))) | |
2635 | } else { | |
2636 | None | |
2637 | } | |
2638 | }, | |
2639 | fat_arrow_token: input.parse()?, | |
2640 | body: { | |
2641 | let body = input.call(expr_early)?; | |
2642 | requires_comma = requires_terminator(&body); | |
2643 | Box::new(body) | |
2644 | }, | |
2645 | comma: { | |
2646 | if requires_comma && !input.is_empty() { | |
2647 | Some(input.parse()?) | |
2648 | } else { | |
2649 | input.parse()? | |
2650 | } | |
2651 | }, | |
2652 | }) | |
2653 | } | |
2654 | } | |
2655 | ||
2656 | impl Parse for Index { | |
2657 | fn parse(input: ParseStream) -> Result<Self> { | |
2658 | let lit: LitInt = input.parse()?; | |
2659 | if lit.suffix().is_empty() { | |
2660 | Ok(Index { | |
2661 | index: lit | |
2662 | .base10_digits() | |
2663 | .parse() | |
2664 | .map_err(|err| Error::new(lit.span(), err))?, | |
2665 | span: lit.span(), | |
2666 | }) | |
2667 | } else { | |
2668 | Err(Error::new(lit.span(), "expected unsuffixed integer")) | |
2669 | } | |
2670 | } | |
2671 | } | |
2672 | ||
2673 | #[cfg(feature = "full")] | |
2674 | impl Member { | |
2675 | fn is_named(&self) -> bool { | |
2676 | match *self { | |
2677 | Member::Named(_) => true, | |
2678 | Member::Unnamed(_) => false, | |
2679 | } | |
2680 | } | |
2681 | } | |
2682 | } | |
2683 | ||
2684 | #[cfg(feature = "printing")] | |
2685 | pub(crate) mod printing { | |
2686 | use super::*; | |
2687 | ||
2688 | use proc_macro2::{Literal, TokenStream}; | |
2689 | use quote::{ToTokens, TokenStreamExt}; | |
2690 | ||
2691 | #[cfg(feature = "full")] | |
2692 | use crate::attr::FilterAttrs; | |
2693 | #[cfg(feature = "full")] | |
2694 | use crate::print::TokensOrDefault; | |
2695 | ||
2696 | // If the given expression is a bare `ExprStruct`, wraps it in parenthesis | |
2697 | // before appending it to `TokenStream`. | |
2698 | #[cfg(feature = "full")] | |
2699 | fn wrap_bare_struct(tokens: &mut TokenStream, e: &Expr) { | |
2700 | if let Expr::Struct(_) = *e { | |
2701 | token::Paren::default().surround(tokens, |tokens| { | |
2702 | e.to_tokens(tokens); | |
2703 | }); | |
2704 | } else { | |
2705 | e.to_tokens(tokens); | |
2706 | } | |
2707 | } | |
2708 | ||
2709 | #[cfg(feature = "full")] | |
2710 | pub(crate) fn outer_attrs_to_tokens(attrs: &[Attribute], tokens: &mut TokenStream) { | |
2711 | tokens.append_all(attrs.outer()); | |
2712 | } | |
2713 | ||
2714 | #[cfg(feature = "full")] | |
2715 | fn inner_attrs_to_tokens(attrs: &[Attribute], tokens: &mut TokenStream) { | |
2716 | tokens.append_all(attrs.inner()); | |
2717 | } | |
2718 | ||
2719 | #[cfg(not(feature = "full"))] | |
2720 | pub(crate) fn outer_attrs_to_tokens(_attrs: &[Attribute], _tokens: &mut TokenStream) {} | |
2721 | ||
2722 | #[cfg(not(feature = "full"))] | |
2723 | fn inner_attrs_to_tokens(_attrs: &[Attribute], _tokens: &mut TokenStream) {} | |
2724 | ||
2725 | #[cfg(feature = "full")] | |
2726 | impl ToTokens for ExprBox { | |
2727 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2728 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2729 | self.box_token.to_tokens(tokens); | |
2730 | self.expr.to_tokens(tokens); | |
2731 | } | |
2732 | } | |
2733 | ||
2734 | #[cfg(feature = "full")] | |
2735 | impl ToTokens for ExprArray { | |
2736 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2737 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2738 | self.bracket_token.surround(tokens, |tokens| { | |
2739 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2740 | self.elems.to_tokens(tokens); | |
2741 | }) | |
2742 | } | |
2743 | } | |
2744 | ||
2745 | impl ToTokens for ExprCall { | |
2746 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2747 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2748 | self.func.to_tokens(tokens); | |
2749 | self.paren_token.surround(tokens, |tokens| { | |
2750 | self.args.to_tokens(tokens); | |
2751 | }) | |
2752 | } | |
2753 | } | |
2754 | ||
2755 | #[cfg(feature = "full")] | |
2756 | impl ToTokens for ExprMethodCall { | |
2757 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2758 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2759 | self.receiver.to_tokens(tokens); | |
2760 | self.dot_token.to_tokens(tokens); | |
2761 | self.method.to_tokens(tokens); | |
2762 | self.turbofish.to_tokens(tokens); | |
2763 | self.paren_token.surround(tokens, |tokens| { | |
2764 | self.args.to_tokens(tokens); | |
2765 | }); | |
2766 | } | |
2767 | } | |
2768 | ||
2769 | #[cfg(feature = "full")] | |
2770 | impl ToTokens for MethodTurbofish { | |
2771 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2772 | self.colon2_token.to_tokens(tokens); | |
2773 | self.lt_token.to_tokens(tokens); | |
2774 | self.args.to_tokens(tokens); | |
2775 | self.gt_token.to_tokens(tokens); | |
2776 | } | |
2777 | } | |
2778 | ||
2779 | #[cfg(feature = "full")] | |
2780 | impl ToTokens for GenericMethodArgument { | |
2781 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2782 | match self { | |
2783 | GenericMethodArgument::Type(t) => t.to_tokens(tokens), | |
2784 | GenericMethodArgument::Const(c) => c.to_tokens(tokens), | |
2785 | } | |
2786 | } | |
2787 | } | |
2788 | ||
2789 | #[cfg(feature = "full")] | |
2790 | impl ToTokens for ExprTuple { | |
2791 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2792 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2793 | self.paren_token.surround(tokens, |tokens| { | |
2794 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2795 | self.elems.to_tokens(tokens); | |
2796 | // If we only have one argument, we need a trailing comma to | |
2797 | // distinguish ExprTuple from ExprParen. | |
2798 | if self.elems.len() == 1 && !self.elems.trailing_punct() { | |
2799 | <Token![,]>::default().to_tokens(tokens); | |
2800 | } | |
2801 | }) | |
2802 | } | |
2803 | } | |
2804 | ||
2805 | impl ToTokens for ExprBinary { | |
2806 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2807 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2808 | self.left.to_tokens(tokens); | |
2809 | self.op.to_tokens(tokens); | |
2810 | self.right.to_tokens(tokens); | |
2811 | } | |
2812 | } | |
2813 | ||
2814 | impl ToTokens for ExprUnary { | |
2815 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2816 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2817 | self.op.to_tokens(tokens); | |
2818 | self.expr.to_tokens(tokens); | |
2819 | } | |
2820 | } | |
2821 | ||
2822 | impl ToTokens for ExprLit { | |
2823 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2824 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2825 | self.lit.to_tokens(tokens); | |
2826 | } | |
2827 | } | |
2828 | ||
2829 | impl ToTokens for ExprCast { | |
2830 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2831 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2832 | self.expr.to_tokens(tokens); | |
2833 | self.as_token.to_tokens(tokens); | |
2834 | self.ty.to_tokens(tokens); | |
2835 | } | |
2836 | } | |
2837 | ||
2838 | #[cfg(feature = "full")] | |
2839 | impl ToTokens for ExprType { | |
2840 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2841 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2842 | self.expr.to_tokens(tokens); | |
2843 | self.colon_token.to_tokens(tokens); | |
2844 | self.ty.to_tokens(tokens); | |
2845 | } | |
2846 | } | |
2847 | ||
2848 | #[cfg(feature = "full")] | |
2849 | fn maybe_wrap_else(tokens: &mut TokenStream, else_: &Option<(Token![else], Box<Expr>)>) { | |
2850 | if let Some((else_token, else_)) = else_ { | |
2851 | else_token.to_tokens(tokens); | |
2852 | ||
2853 | // If we are not one of the valid expressions to exist in an else | |
2854 | // clause, wrap ourselves in a block. | |
2855 | match **else_ { | |
2856 | Expr::If(_) | Expr::Block(_) => { | |
2857 | else_.to_tokens(tokens); | |
2858 | } | |
2859 | _ => { | |
2860 | token::Brace::default().surround(tokens, |tokens| { | |
2861 | else_.to_tokens(tokens); | |
2862 | }); | |
2863 | } | |
2864 | } | |
2865 | } | |
2866 | } | |
2867 | ||
2868 | #[cfg(feature = "full")] | |
2869 | impl ToTokens for ExprLet { | |
2870 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2871 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2872 | self.let_token.to_tokens(tokens); | |
2873 | self.pat.to_tokens(tokens); | |
2874 | self.eq_token.to_tokens(tokens); | |
2875 | wrap_bare_struct(tokens, &self.expr); | |
2876 | } | |
2877 | } | |
2878 | ||
2879 | #[cfg(feature = "full")] | |
2880 | impl ToTokens for ExprIf { | |
2881 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2882 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2883 | self.if_token.to_tokens(tokens); | |
2884 | wrap_bare_struct(tokens, &self.cond); | |
2885 | self.then_branch.to_tokens(tokens); | |
2886 | maybe_wrap_else(tokens, &self.else_branch); | |
2887 | } | |
2888 | } | |
2889 | ||
2890 | #[cfg(feature = "full")] | |
2891 | impl ToTokens for ExprWhile { | |
2892 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2893 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2894 | self.label.to_tokens(tokens); | |
2895 | self.while_token.to_tokens(tokens); | |
2896 | wrap_bare_struct(tokens, &self.cond); | |
2897 | self.body.brace_token.surround(tokens, |tokens| { | |
2898 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2899 | tokens.append_all(&self.body.stmts); | |
2900 | }); | |
2901 | } | |
2902 | } | |
2903 | ||
2904 | #[cfg(feature = "full")] | |
2905 | impl ToTokens for ExprForLoop { | |
2906 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2907 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2908 | self.label.to_tokens(tokens); | |
2909 | self.for_token.to_tokens(tokens); | |
2910 | self.pat.to_tokens(tokens); | |
2911 | self.in_token.to_tokens(tokens); | |
2912 | wrap_bare_struct(tokens, &self.expr); | |
2913 | self.body.brace_token.surround(tokens, |tokens| { | |
2914 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2915 | tokens.append_all(&self.body.stmts); | |
2916 | }); | |
2917 | } | |
2918 | } | |
2919 | ||
2920 | #[cfg(feature = "full")] | |
2921 | impl ToTokens for ExprLoop { | |
2922 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2923 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2924 | self.label.to_tokens(tokens); | |
2925 | self.loop_token.to_tokens(tokens); | |
2926 | self.body.brace_token.surround(tokens, |tokens| { | |
2927 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2928 | tokens.append_all(&self.body.stmts); | |
2929 | }); | |
2930 | } | |
2931 | } | |
2932 | ||
2933 | #[cfg(feature = "full")] | |
2934 | impl ToTokens for ExprMatch { | |
2935 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2936 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2937 | self.match_token.to_tokens(tokens); | |
2938 | wrap_bare_struct(tokens, &self.expr); | |
2939 | self.brace_token.surround(tokens, |tokens| { | |
2940 | inner_attrs_to_tokens(&self.attrs, tokens); | |
2941 | for (i, arm) in self.arms.iter().enumerate() { | |
2942 | arm.to_tokens(tokens); | |
2943 | // Ensure that we have a comma after a non-block arm, except | |
2944 | // for the last one. | |
2945 | let is_last = i == self.arms.len() - 1; | |
2946 | if !is_last && requires_terminator(&arm.body) && arm.comma.is_none() { | |
2947 | <Token![,]>::default().to_tokens(tokens); | |
2948 | } | |
2949 | } | |
2950 | }); | |
2951 | } | |
2952 | } | |
2953 | ||
2954 | #[cfg(feature = "full")] | |
2955 | impl ToTokens for ExprAsync { | |
2956 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2957 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2958 | self.async_token.to_tokens(tokens); | |
2959 | self.capture.to_tokens(tokens); | |
2960 | self.block.to_tokens(tokens); | |
2961 | } | |
2962 | } | |
2963 | ||
2964 | #[cfg(feature = "full")] | |
2965 | impl ToTokens for ExprAwait { | |
2966 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2967 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2968 | self.base.to_tokens(tokens); | |
2969 | self.dot_token.to_tokens(tokens); | |
2970 | self.await_token.to_tokens(tokens); | |
2971 | } | |
2972 | } | |
2973 | ||
2974 | #[cfg(feature = "full")] | |
2975 | impl ToTokens for ExprTryBlock { | |
2976 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2977 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2978 | self.try_token.to_tokens(tokens); | |
2979 | self.block.to_tokens(tokens); | |
2980 | } | |
2981 | } | |
2982 | ||
2983 | #[cfg(feature = "full")] | |
2984 | impl ToTokens for ExprYield { | |
2985 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2986 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2987 | self.yield_token.to_tokens(tokens); | |
2988 | self.expr.to_tokens(tokens); | |
2989 | } | |
2990 | } | |
2991 | ||
2992 | #[cfg(feature = "full")] | |
2993 | impl ToTokens for ExprClosure { | |
2994 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
2995 | outer_attrs_to_tokens(&self.attrs, tokens); | |
2996 | self.asyncness.to_tokens(tokens); | |
2997 | self.movability.to_tokens(tokens); | |
2998 | self.capture.to_tokens(tokens); | |
2999 | self.or1_token.to_tokens(tokens); | |
3000 | self.inputs.to_tokens(tokens); | |
3001 | self.or2_token.to_tokens(tokens); | |
3002 | self.output.to_tokens(tokens); | |
3003 | self.body.to_tokens(tokens); | |
3004 | } | |
3005 | } | |
3006 | ||
3007 | #[cfg(feature = "full")] | |
3008 | impl ToTokens for ExprUnsafe { | |
3009 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3010 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3011 | self.unsafe_token.to_tokens(tokens); | |
3012 | self.block.brace_token.surround(tokens, |tokens| { | |
3013 | inner_attrs_to_tokens(&self.attrs, tokens); | |
3014 | tokens.append_all(&self.block.stmts); | |
3015 | }); | |
3016 | } | |
3017 | } | |
3018 | ||
3019 | #[cfg(feature = "full")] | |
3020 | impl ToTokens for ExprBlock { | |
3021 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3022 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3023 | self.label.to_tokens(tokens); | |
3024 | self.block.brace_token.surround(tokens, |tokens| { | |
3025 | inner_attrs_to_tokens(&self.attrs, tokens); | |
3026 | tokens.append_all(&self.block.stmts); | |
3027 | }); | |
3028 | } | |
3029 | } | |
3030 | ||
3031 | #[cfg(feature = "full")] | |
3032 | impl ToTokens for ExprAssign { | |
3033 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3034 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3035 | self.left.to_tokens(tokens); | |
3036 | self.eq_token.to_tokens(tokens); | |
3037 | self.right.to_tokens(tokens); | |
3038 | } | |
3039 | } | |
3040 | ||
3041 | #[cfg(feature = "full")] | |
3042 | impl ToTokens for ExprAssignOp { | |
3043 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3044 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3045 | self.left.to_tokens(tokens); | |
3046 | self.op.to_tokens(tokens); | |
3047 | self.right.to_tokens(tokens); | |
3048 | } | |
3049 | } | |
3050 | ||
3051 | impl ToTokens for ExprField { | |
3052 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3053 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3054 | self.base.to_tokens(tokens); | |
3055 | self.dot_token.to_tokens(tokens); | |
3056 | self.member.to_tokens(tokens); | |
3057 | } | |
3058 | } | |
3059 | ||
3060 | impl ToTokens for Member { | |
3061 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3062 | match self { | |
3063 | Member::Named(ident) => ident.to_tokens(tokens), | |
3064 | Member::Unnamed(index) => index.to_tokens(tokens), | |
3065 | } | |
3066 | } | |
3067 | } | |
3068 | ||
3069 | impl ToTokens for Index { | |
3070 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3071 | let mut lit = Literal::i64_unsuffixed(i64::from(self.index)); | |
3072 | lit.set_span(self.span); | |
3073 | tokens.append(lit); | |
3074 | } | |
3075 | } | |
3076 | ||
3077 | impl ToTokens for ExprIndex { | |
3078 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3079 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3080 | self.expr.to_tokens(tokens); | |
3081 | self.bracket_token.surround(tokens, |tokens| { | |
3082 | self.index.to_tokens(tokens); | |
3083 | }); | |
3084 | } | |
3085 | } | |
3086 | ||
3087 | #[cfg(feature = "full")] | |
3088 | impl ToTokens for ExprRange { | |
3089 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3090 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3091 | self.from.to_tokens(tokens); | |
3092 | match &self.limits { | |
3093 | RangeLimits::HalfOpen(t) => t.to_tokens(tokens), | |
3094 | RangeLimits::Closed(t) => t.to_tokens(tokens), | |
3095 | } | |
3096 | self.to.to_tokens(tokens); | |
3097 | } | |
3098 | } | |
3099 | ||
3100 | impl ToTokens for ExprPath { | |
3101 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3102 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3103 | private::print_path(tokens, &self.qself, &self.path); | |
3104 | } | |
3105 | } | |
3106 | ||
3107 | #[cfg(feature = "full")] | |
3108 | impl ToTokens for ExprReference { | |
3109 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3110 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3111 | self.and_token.to_tokens(tokens); | |
3112 | self.mutability.to_tokens(tokens); | |
3113 | self.expr.to_tokens(tokens); | |
3114 | } | |
3115 | } | |
3116 | ||
3117 | #[cfg(feature = "full")] | |
3118 | impl ToTokens for ExprBreak { | |
3119 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3120 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3121 | self.break_token.to_tokens(tokens); | |
3122 | self.label.to_tokens(tokens); | |
3123 | self.expr.to_tokens(tokens); | |
3124 | } | |
3125 | } | |
3126 | ||
3127 | #[cfg(feature = "full")] | |
3128 | impl ToTokens for ExprContinue { | |
3129 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3130 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3131 | self.continue_token.to_tokens(tokens); | |
3132 | self.label.to_tokens(tokens); | |
3133 | } | |
3134 | } | |
3135 | ||
3136 | #[cfg(feature = "full")] | |
3137 | impl ToTokens for ExprReturn { | |
3138 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3139 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3140 | self.return_token.to_tokens(tokens); | |
3141 | self.expr.to_tokens(tokens); | |
3142 | } | |
3143 | } | |
3144 | ||
3145 | #[cfg(feature = "full")] | |
3146 | impl ToTokens for ExprMacro { | |
3147 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3148 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3149 | self.mac.to_tokens(tokens); | |
3150 | } | |
3151 | } | |
3152 | ||
3153 | #[cfg(feature = "full")] | |
3154 | impl ToTokens for ExprStruct { | |
3155 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3156 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3157 | self.path.to_tokens(tokens); | |
3158 | self.brace_token.surround(tokens, |tokens| { | |
3159 | inner_attrs_to_tokens(&self.attrs, tokens); | |
3160 | self.fields.to_tokens(tokens); | |
3161 | if self.rest.is_some() { | |
3162 | TokensOrDefault(&self.dot2_token).to_tokens(tokens); | |
3163 | self.rest.to_tokens(tokens); | |
3164 | } | |
3165 | }) | |
3166 | } | |
3167 | } | |
3168 | ||
3169 | #[cfg(feature = "full")] | |
3170 | impl ToTokens for ExprRepeat { | |
3171 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3172 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3173 | self.bracket_token.surround(tokens, |tokens| { | |
3174 | inner_attrs_to_tokens(&self.attrs, tokens); | |
3175 | self.expr.to_tokens(tokens); | |
3176 | self.semi_token.to_tokens(tokens); | |
3177 | self.len.to_tokens(tokens); | |
3178 | }) | |
3179 | } | |
3180 | } | |
3181 | ||
3182 | #[cfg(feature = "full")] | |
3183 | impl ToTokens for ExprGroup { | |
3184 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3185 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3186 | self.group_token.surround(tokens, |tokens| { | |
3187 | self.expr.to_tokens(tokens); | |
3188 | }); | |
3189 | } | |
3190 | } | |
3191 | ||
3192 | impl ToTokens for ExprParen { | |
3193 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3194 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3195 | self.paren_token.surround(tokens, |tokens| { | |
3196 | inner_attrs_to_tokens(&self.attrs, tokens); | |
3197 | self.expr.to_tokens(tokens); | |
3198 | }); | |
3199 | } | |
3200 | } | |
3201 | ||
3202 | #[cfg(feature = "full")] | |
3203 | impl ToTokens for ExprTry { | |
3204 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3205 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3206 | self.expr.to_tokens(tokens); | |
3207 | self.question_token.to_tokens(tokens); | |
3208 | } | |
3209 | } | |
3210 | ||
3211 | #[cfg(feature = "full")] | |
3212 | impl ToTokens for Label { | |
3213 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3214 | self.name.to_tokens(tokens); | |
3215 | self.colon_token.to_tokens(tokens); | |
3216 | } | |
3217 | } | |
3218 | ||
3219 | #[cfg(feature = "full")] | |
3220 | impl ToTokens for FieldValue { | |
3221 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3222 | outer_attrs_to_tokens(&self.attrs, tokens); | |
3223 | self.member.to_tokens(tokens); | |
3224 | if let Some(colon_token) = &self.colon_token { | |
3225 | colon_token.to_tokens(tokens); | |
3226 | self.expr.to_tokens(tokens); | |
3227 | } | |
3228 | } | |
3229 | } | |
3230 | ||
3231 | #[cfg(feature = "full")] | |
3232 | impl ToTokens for Arm { | |
3233 | fn to_tokens(&self, tokens: &mut TokenStream) { | |
3234 | tokens.append_all(&self.attrs); | |
3235 | self.pat.to_tokens(tokens); | |
3236 | if let Some((if_token, guard)) = &self.guard { | |
3237 | if_token.to_tokens(tokens); | |
3238 | guard.to_tokens(tokens); | |
3239 | } | |
3240 | self.fat_arrow_token.to_tokens(tokens); | |
3241 | self.body.to_tokens(tokens); | |
3242 | self.comma.to_tokens(tokens); | |
3243 | } | |
3244 | } | |
3245 | } |