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New upstream version 1.22.1+dfsg1
[rustc.git] / src / libsyntax / print / pprust.rs
1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
4 //
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
10
11 pub use self::AnnNode::*;
12
13 use abi::{self, Abi};
14 use ast::{self, BlockCheckMode, PatKind, RangeEnd, RangeSyntax};
15 use ast::{SelfKind, RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
16 use ast::Attribute;
17 use util::parser::{self, AssocOp, Fixity};
18 use attr;
19 use codemap::{self, CodeMap};
20 use syntax_pos::{self, BytePos};
21 use parse::token::{self, BinOpToken, Token};
22 use parse::lexer::comments;
23 use parse::{self, ParseSess};
24 use print::pp::{self, Breaks};
25 use print::pp::Breaks::{Consistent, Inconsistent};
26 use ptr::P;
27 use std_inject;
28 use symbol::{Symbol, keywords};
29 use syntax_pos::DUMMY_SP;
30 use tokenstream::{self, TokenStream, TokenTree};
31
32 use std::ascii;
33 use std::io::{self, Write, Read};
34 use std::iter::{self, Peekable};
35 use std::vec;
36
37 pub enum AnnNode<'a> {
38 NodeIdent(&'a ast::Ident),
39 NodeName(&'a ast::Name),
40 NodeBlock(&'a ast::Block),
41 NodeItem(&'a ast::Item),
42 NodeSubItem(ast::NodeId),
43 NodeExpr(&'a ast::Expr),
44 NodePat(&'a ast::Pat),
45 }
46
47 pub trait PpAnn {
48 fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
49 fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
50 }
51
52 #[derive(Copy, Clone)]
53 pub struct NoAnn;
54
55 impl PpAnn for NoAnn {}
56
57 pub struct State<'a> {
58 pub s: pp::Printer<'a>,
59 cm: Option<&'a CodeMap>,
60 comments: Option<Vec<comments::Comment> >,
61 literals: Peekable<vec::IntoIter<comments::Literal>>,
62 cur_cmnt: usize,
63 boxes: Vec<pp::Breaks>,
64 ann: &'a (PpAnn+'a),
65 }
66
67 fn rust_printer<'a>(writer: Box<Write+'a>, ann: &'a PpAnn) -> State<'a> {
68 State {
69 s: pp::mk_printer(writer, DEFAULT_COLUMNS),
70 cm: None,
71 comments: None,
72 literals: vec![].into_iter().peekable(),
73 cur_cmnt: 0,
74 boxes: Vec::new(),
75 ann,
76 }
77 }
78
79 pub const INDENT_UNIT: usize = 4;
80
81 pub const DEFAULT_COLUMNS: usize = 78;
82
83 /// Requires you to pass an input filename and reader so that
84 /// it can scan the input text for comments and literals to
85 /// copy forward.
86 pub fn print_crate<'a>(cm: &'a CodeMap,
87 sess: &ParseSess,
88 krate: &ast::Crate,
89 filename: String,
90 input: &mut Read,
91 out: Box<Write+'a>,
92 ann: &'a PpAnn,
93 is_expanded: bool) -> io::Result<()> {
94 let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded);
95
96 if is_expanded && !std_inject::injected_crate_name(krate).is_none() {
97 // We need to print `#![no_std]` (and its feature gate) so that
98 // compiling pretty-printed source won't inject libstd again.
99 // However we don't want these attributes in the AST because
100 // of the feature gate, so we fake them up here.
101
102 // #![feature(prelude_import)]
103 let prelude_import_meta = attr::mk_list_word_item(Symbol::intern("prelude_import"));
104 let list = attr::mk_list_item(Symbol::intern("feature"), vec![prelude_import_meta]);
105 let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), list);
106 s.print_attribute(&fake_attr)?;
107
108 // #![no_std]
109 let no_std_meta = attr::mk_word_item(Symbol::intern("no_std"));
110 let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), no_std_meta);
111 s.print_attribute(&fake_attr)?;
112 }
113
114 s.print_mod(&krate.module, &krate.attrs)?;
115 s.print_remaining_comments()?;
116 s.s.eof()
117 }
118
119 impl<'a> State<'a> {
120 pub fn new_from_input(cm: &'a CodeMap,
121 sess: &ParseSess,
122 filename: String,
123 input: &mut Read,
124 out: Box<Write+'a>,
125 ann: &'a PpAnn,
126 is_expanded: bool) -> State<'a> {
127 let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input);
128
129 State::new(
130 cm,
131 out,
132 ann,
133 Some(cmnts),
134 // If the code is post expansion, don't use the table of
135 // literals, since it doesn't correspond with the literals
136 // in the AST anymore.
137 if is_expanded { None } else { Some(lits) })
138 }
139
140 pub fn new(cm: &'a CodeMap,
141 out: Box<Write+'a>,
142 ann: &'a PpAnn,
143 comments: Option<Vec<comments::Comment>>,
144 literals: Option<Vec<comments::Literal>>) -> State<'a> {
145 State {
146 s: pp::mk_printer(out, DEFAULT_COLUMNS),
147 cm: Some(cm),
148 comments,
149 literals: literals.unwrap_or_default().into_iter().peekable(),
150 cur_cmnt: 0,
151 boxes: Vec::new(),
152 ann,
153 }
154 }
155 }
156
157 pub fn to_string<F>(f: F) -> String where
158 F: FnOnce(&mut State) -> io::Result<()>,
159 {
160 let mut wr = Vec::new();
161 {
162 let ann = NoAnn;
163 let mut printer = rust_printer(Box::new(&mut wr), &ann);
164 f(&mut printer).unwrap();
165 printer.s.eof().unwrap();
166 }
167 String::from_utf8(wr).unwrap()
168 }
169
170 fn binop_to_string(op: BinOpToken) -> &'static str {
171 match op {
172 token::Plus => "+",
173 token::Minus => "-",
174 token::Star => "*",
175 token::Slash => "/",
176 token::Percent => "%",
177 token::Caret => "^",
178 token::And => "&",
179 token::Or => "|",
180 token::Shl => "<<",
181 token::Shr => ">>",
182 }
183 }
184
185 pub fn token_to_string(tok: &Token) -> String {
186 match *tok {
187 token::Eq => "=".to_string(),
188 token::Lt => "<".to_string(),
189 token::Le => "<=".to_string(),
190 token::EqEq => "==".to_string(),
191 token::Ne => "!=".to_string(),
192 token::Ge => ">=".to_string(),
193 token::Gt => ">".to_string(),
194 token::Not => "!".to_string(),
195 token::Tilde => "~".to_string(),
196 token::OrOr => "||".to_string(),
197 token::AndAnd => "&&".to_string(),
198 token::BinOp(op) => binop_to_string(op).to_string(),
199 token::BinOpEq(op) => format!("{}=", binop_to_string(op)),
200
201 /* Structural symbols */
202 token::At => "@".to_string(),
203 token::Dot => ".".to_string(),
204 token::DotDot => "..".to_string(),
205 token::DotDotDot => "...".to_string(),
206 token::DotDotEq => "..=".to_string(),
207 token::DotEq => ".=".to_string(),
208 token::Comma => ",".to_string(),
209 token::Semi => ";".to_string(),
210 token::Colon => ":".to_string(),
211 token::ModSep => "::".to_string(),
212 token::RArrow => "->".to_string(),
213 token::LArrow => "<-".to_string(),
214 token::FatArrow => "=>".to_string(),
215 token::OpenDelim(token::Paren) => "(".to_string(),
216 token::CloseDelim(token::Paren) => ")".to_string(),
217 token::OpenDelim(token::Bracket) => "[".to_string(),
218 token::CloseDelim(token::Bracket) => "]".to_string(),
219 token::OpenDelim(token::Brace) => "{".to_string(),
220 token::CloseDelim(token::Brace) => "}".to_string(),
221 token::OpenDelim(token::NoDelim) |
222 token::CloseDelim(token::NoDelim) => " ".to_string(),
223 token::Pound => "#".to_string(),
224 token::Dollar => "$".to_string(),
225 token::Question => "?".to_string(),
226
227 /* Literals */
228 token::Literal(lit, suf) => {
229 let mut out = match lit {
230 token::Byte(b) => format!("b'{}'", b),
231 token::Char(c) => format!("'{}'", c),
232 token::Float(c) |
233 token::Integer(c) => c.to_string(),
234 token::Str_(s) => format!("\"{}\"", s),
235 token::StrRaw(s, n) => format!("r{delim}\"{string}\"{delim}",
236 delim=repeat("#", n),
237 string=s),
238 token::ByteStr(v) => format!("b\"{}\"", v),
239 token::ByteStrRaw(s, n) => format!("br{delim}\"{string}\"{delim}",
240 delim=repeat("#", n),
241 string=s),
242 };
243
244 if let Some(s) = suf {
245 out.push_str(&s.as_str())
246 }
247
248 out
249 }
250
251 /* Name components */
252 token::Ident(s) => s.to_string(),
253 token::Lifetime(s) => s.to_string(),
254 token::Underscore => "_".to_string(),
255
256 /* Other */
257 token::DocComment(s) => s.to_string(),
258 token::Eof => "<eof>".to_string(),
259 token::Whitespace => " ".to_string(),
260 token::Comment => "/* */".to_string(),
261 token::Shebang(s) => format!("/* shebang: {}*/", s),
262
263 token::Interpolated(ref nt) => match nt.0 {
264 token::NtExpr(ref e) => expr_to_string(e),
265 token::NtMeta(ref e) => meta_item_to_string(e),
266 token::NtTy(ref e) => ty_to_string(e),
267 token::NtPath(ref e) => path_to_string(e),
268 token::NtItem(ref e) => item_to_string(e),
269 token::NtBlock(ref e) => block_to_string(e),
270 token::NtStmt(ref e) => stmt_to_string(e),
271 token::NtPat(ref e) => pat_to_string(e),
272 token::NtIdent(ref e) => ident_to_string(e.node),
273 token::NtTT(ref tree) => tt_to_string(tree.clone()),
274 token::NtArm(ref e) => arm_to_string(e),
275 token::NtImplItem(ref e) => impl_item_to_string(e),
276 token::NtTraitItem(ref e) => trait_item_to_string(e),
277 token::NtGenerics(ref e) => generics_to_string(e),
278 token::NtWhereClause(ref e) => where_clause_to_string(e),
279 token::NtArg(ref e) => arg_to_string(e),
280 token::NtVis(ref e) => vis_to_string(e),
281 }
282 }
283 }
284
285 pub fn ty_to_string(ty: &ast::Ty) -> String {
286 to_string(|s| s.print_type(ty))
287 }
288
289 pub fn bounds_to_string(bounds: &[ast::TyParamBound]) -> String {
290 to_string(|s| s.print_bounds("", bounds))
291 }
292
293 pub fn pat_to_string(pat: &ast::Pat) -> String {
294 to_string(|s| s.print_pat(pat))
295 }
296
297 pub fn arm_to_string(arm: &ast::Arm) -> String {
298 to_string(|s| s.print_arm(arm))
299 }
300
301 pub fn expr_to_string(e: &ast::Expr) -> String {
302 to_string(|s| s.print_expr(e))
303 }
304
305 pub fn lifetime_to_string(e: &ast::Lifetime) -> String {
306 to_string(|s| s.print_lifetime(e))
307 }
308
309 pub fn tt_to_string(tt: tokenstream::TokenTree) -> String {
310 to_string(|s| s.print_tt(tt))
311 }
312
313 pub fn tts_to_string(tts: &[tokenstream::TokenTree]) -> String {
314 to_string(|s| s.print_tts(tts.iter().cloned().collect()))
315 }
316
317 pub fn tokens_to_string(tokens: TokenStream) -> String {
318 to_string(|s| s.print_tts(tokens))
319 }
320
321 pub fn stmt_to_string(stmt: &ast::Stmt) -> String {
322 to_string(|s| s.print_stmt(stmt))
323 }
324
325 pub fn attr_to_string(attr: &ast::Attribute) -> String {
326 to_string(|s| s.print_attribute(attr))
327 }
328
329 pub fn item_to_string(i: &ast::Item) -> String {
330 to_string(|s| s.print_item(i))
331 }
332
333 pub fn impl_item_to_string(i: &ast::ImplItem) -> String {
334 to_string(|s| s.print_impl_item(i))
335 }
336
337 pub fn trait_item_to_string(i: &ast::TraitItem) -> String {
338 to_string(|s| s.print_trait_item(i))
339 }
340
341 pub fn generics_to_string(generics: &ast::Generics) -> String {
342 to_string(|s| s.print_generics(generics))
343 }
344
345 pub fn where_clause_to_string(i: &ast::WhereClause) -> String {
346 to_string(|s| s.print_where_clause(i))
347 }
348
349 pub fn fn_block_to_string(p: &ast::FnDecl) -> String {
350 to_string(|s| s.print_fn_block_args(p))
351 }
352
353 pub fn path_to_string(p: &ast::Path) -> String {
354 to_string(|s| s.print_path(p, false, 0, false))
355 }
356
357 pub fn path_segment_to_string(p: &ast::PathSegment) -> String {
358 to_string(|s| s.print_path_segment(p, false))
359 }
360
361 pub fn ident_to_string(id: ast::Ident) -> String {
362 to_string(|s| s.print_ident(id))
363 }
364
365 pub fn vis_to_string(v: &ast::Visibility) -> String {
366 to_string(|s| s.print_visibility(v))
367 }
368
369 pub fn fun_to_string(decl: &ast::FnDecl,
370 unsafety: ast::Unsafety,
371 constness: ast::Constness,
372 name: ast::Ident,
373 generics: &ast::Generics)
374 -> String {
375 to_string(|s| {
376 s.head("")?;
377 s.print_fn(decl, unsafety, constness, Abi::Rust, Some(name),
378 generics, &ast::Visibility::Inherited)?;
379 s.end()?; // Close the head box
380 s.end() // Close the outer box
381 })
382 }
383
384 pub fn block_to_string(blk: &ast::Block) -> String {
385 to_string(|s| {
386 // containing cbox, will be closed by print-block at }
387 s.cbox(INDENT_UNIT)?;
388 // head-ibox, will be closed by print-block after {
389 s.ibox(0)?;
390 s.print_block(blk)
391 })
392 }
393
394 pub fn meta_list_item_to_string(li: &ast::NestedMetaItem) -> String {
395 to_string(|s| s.print_meta_list_item(li))
396 }
397
398 pub fn meta_item_to_string(mi: &ast::MetaItem) -> String {
399 to_string(|s| s.print_meta_item(mi))
400 }
401
402 pub fn attribute_to_string(attr: &ast::Attribute) -> String {
403 to_string(|s| s.print_attribute(attr))
404 }
405
406 pub fn lit_to_string(l: &ast::Lit) -> String {
407 to_string(|s| s.print_literal(l))
408 }
409
410 pub fn variant_to_string(var: &ast::Variant) -> String {
411 to_string(|s| s.print_variant(var))
412 }
413
414 pub fn arg_to_string(arg: &ast::Arg) -> String {
415 to_string(|s| s.print_arg(arg, false))
416 }
417
418 pub fn mac_to_string(arg: &ast::Mac) -> String {
419 to_string(|s| s.print_mac(arg, ::parse::token::Paren))
420 }
421
422 pub fn visibility_qualified(vis: &ast::Visibility, s: &str) -> String {
423 format!("{}{}", to_string(|s| s.print_visibility(vis)), s)
424 }
425
426 pub trait PrintState<'a> {
427 fn writer(&mut self) -> &mut pp::Printer<'a>;
428 fn boxes(&mut self) -> &mut Vec<pp::Breaks>;
429 fn comments(&mut self) -> &mut Option<Vec<comments::Comment>>;
430 fn cur_cmnt(&mut self) -> &mut usize;
431 fn cur_lit(&mut self) -> Option<&comments::Literal>;
432 fn bump_lit(&mut self) -> Option<comments::Literal>;
433
434 fn word_space(&mut self, w: &str) -> io::Result<()> {
435 self.writer().word(w)?;
436 self.writer().space()
437 }
438
439 fn popen(&mut self) -> io::Result<()> { self.writer().word("(") }
440
441 fn pclose(&mut self) -> io::Result<()> { self.writer().word(")") }
442
443 fn is_begin(&mut self) -> bool {
444 match self.writer().last_token() {
445 pp::Token::Begin(_) => true,
446 _ => false,
447 }
448 }
449
450 fn is_end(&mut self) -> bool {
451 match self.writer().last_token() {
452 pp::Token::End => true,
453 _ => false,
454 }
455 }
456
457 // is this the beginning of a line?
458 fn is_bol(&mut self) -> bool {
459 self.writer().last_token().is_eof() || self.writer().last_token().is_hardbreak_tok()
460 }
461
462 fn hardbreak_if_not_bol(&mut self) -> io::Result<()> {
463 if !self.is_bol() {
464 self.writer().hardbreak()?
465 }
466 Ok(())
467 }
468
469 // "raw box"
470 fn rbox(&mut self, u: usize, b: pp::Breaks) -> io::Result<()> {
471 self.boxes().push(b);
472 self.writer().rbox(u, b)
473 }
474
475 fn ibox(&mut self, u: usize) -> io::Result<()> {
476 self.boxes().push(pp::Breaks::Inconsistent);
477 self.writer().ibox(u)
478 }
479
480 fn end(&mut self) -> io::Result<()> {
481 self.boxes().pop().unwrap();
482 self.writer().end()
483 }
484
485 fn commasep<T, F>(&mut self, b: Breaks, elts: &[T], mut op: F) -> io::Result<()>
486 where F: FnMut(&mut Self, &T) -> io::Result<()>,
487 {
488 self.rbox(0, b)?;
489 let mut first = true;
490 for elt in elts {
491 if first { first = false; } else { self.word_space(",")?; }
492 op(self, elt)?;
493 }
494 self.end()
495 }
496
497 fn next_lit(&mut self, pos: BytePos) -> Option<comments::Literal> {
498 while let Some(ltrl) = self.cur_lit().cloned() {
499 if ltrl.pos > pos { break; }
500
501 // we don't need the value here since we're forced to clone cur_lit
502 // due to lack of NLL.
503 self.bump_lit();
504 if ltrl.pos == pos {
505 return Some(ltrl);
506 }
507 }
508
509 None
510 }
511
512 fn maybe_print_comment(&mut self, pos: BytePos) -> io::Result<()> {
513 while let Some(ref cmnt) = self.next_comment() {
514 if cmnt.pos < pos {
515 self.print_comment(cmnt)?;
516 } else {
517 break
518 }
519 }
520 Ok(())
521 }
522
523 fn print_comment(&mut self,
524 cmnt: &comments::Comment) -> io::Result<()> {
525 let r = match cmnt.style {
526 comments::Mixed => {
527 assert_eq!(cmnt.lines.len(), 1);
528 self.writer().zerobreak()?;
529 self.writer().word(&cmnt.lines[0])?;
530 self.writer().zerobreak()
531 }
532 comments::Isolated => {
533 self.hardbreak_if_not_bol()?;
534 for line in &cmnt.lines {
535 // Don't print empty lines because they will end up as trailing
536 // whitespace
537 if !line.is_empty() {
538 self.writer().word(&line[..])?;
539 }
540 self.writer().hardbreak()?;
541 }
542 Ok(())
543 }
544 comments::Trailing => {
545 if !self.is_bol() {
546 self.writer().word(" ")?;
547 }
548 if cmnt.lines.len() == 1 {
549 self.writer().word(&cmnt.lines[0])?;
550 self.writer().hardbreak()
551 } else {
552 self.ibox(0)?;
553 for line in &cmnt.lines {
554 if !line.is_empty() {
555 self.writer().word(&line[..])?;
556 }
557 self.writer().hardbreak()?;
558 }
559 self.end()
560 }
561 }
562 comments::BlankLine => {
563 // We need to do at least one, possibly two hardbreaks.
564 let is_semi = match self.writer().last_token() {
565 pp::Token::String(s, _) => ";" == s,
566 _ => false
567 };
568 if is_semi || self.is_begin() || self.is_end() {
569 self.writer().hardbreak()?;
570 }
571 self.writer().hardbreak()
572 }
573 };
574 match r {
575 Ok(()) => {
576 *self.cur_cmnt() = *self.cur_cmnt() + 1;
577 Ok(())
578 }
579 Err(e) => Err(e),
580 }
581 }
582
583 fn next_comment(&mut self) -> Option<comments::Comment> {
584 let cur_cmnt = *self.cur_cmnt();
585 match *self.comments() {
586 Some(ref cmnts) => {
587 if cur_cmnt < cmnts.len() {
588 Some(cmnts[cur_cmnt].clone())
589 } else {
590 None
591 }
592 }
593 _ => None
594 }
595 }
596
597 fn print_literal(&mut self, lit: &ast::Lit) -> io::Result<()> {
598 self.maybe_print_comment(lit.span.lo())?;
599 if let Some(ltrl) = self.next_lit(lit.span.lo()) {
600 return self.writer().word(&ltrl.lit);
601 }
602 match lit.node {
603 ast::LitKind::Str(st, style) => self.print_string(&st.as_str(), style),
604 ast::LitKind::Byte(byte) => {
605 let mut res = String::from("b'");
606 res.extend(ascii::escape_default(byte).map(|c| c as char));
607 res.push('\'');
608 self.writer().word(&res[..])
609 }
610 ast::LitKind::Char(ch) => {
611 let mut res = String::from("'");
612 res.extend(ch.escape_default());
613 res.push('\'');
614 self.writer().word(&res[..])
615 }
616 ast::LitKind::Int(i, t) => {
617 match t {
618 ast::LitIntType::Signed(st) => {
619 self.writer().word(&st.val_to_string(i as i128))
620 }
621 ast::LitIntType::Unsigned(ut) => {
622 self.writer().word(&ut.val_to_string(i))
623 }
624 ast::LitIntType::Unsuffixed => {
625 self.writer().word(&format!("{}", i))
626 }
627 }
628 }
629 ast::LitKind::Float(ref f, t) => {
630 self.writer().word(&format!("{}{}", &f, t.ty_to_string()))
631 }
632 ast::LitKind::FloatUnsuffixed(ref f) => self.writer().word(&f.as_str()),
633 ast::LitKind::Bool(val) => {
634 if val { self.writer().word("true") } else { self.writer().word("false") }
635 }
636 ast::LitKind::ByteStr(ref v) => {
637 let mut escaped: String = String::new();
638 for &ch in v.iter() {
639 escaped.extend(ascii::escape_default(ch)
640 .map(|c| c as char));
641 }
642 self.writer().word(&format!("b\"{}\"", escaped))
643 }
644 }
645 }
646
647 fn print_string(&mut self, st: &str,
648 style: ast::StrStyle) -> io::Result<()> {
649 let st = match style {
650 ast::StrStyle::Cooked => {
651 (format!("\"{}\"", parse::escape_default(st)))
652 }
653 ast::StrStyle::Raw(n) => {
654 (format!("r{delim}\"{string}\"{delim}",
655 delim=repeat("#", n),
656 string=st))
657 }
658 };
659 self.writer().word(&st[..])
660 }
661
662 fn print_inner_attributes(&mut self,
663 attrs: &[ast::Attribute]) -> io::Result<()> {
664 self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, true)
665 }
666
667 fn print_inner_attributes_no_trailing_hardbreak(&mut self,
668 attrs: &[ast::Attribute])
669 -> io::Result<()> {
670 self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, false)
671 }
672
673 fn print_outer_attributes(&mut self,
674 attrs: &[ast::Attribute]) -> io::Result<()> {
675 self.print_either_attributes(attrs, ast::AttrStyle::Outer, false, true)
676 }
677
678 fn print_inner_attributes_inline(&mut self,
679 attrs: &[ast::Attribute]) -> io::Result<()> {
680 self.print_either_attributes(attrs, ast::AttrStyle::Inner, true, true)
681 }
682
683 fn print_outer_attributes_inline(&mut self,
684 attrs: &[ast::Attribute]) -> io::Result<()> {
685 self.print_either_attributes(attrs, ast::AttrStyle::Outer, true, true)
686 }
687
688 fn print_either_attributes(&mut self,
689 attrs: &[ast::Attribute],
690 kind: ast::AttrStyle,
691 is_inline: bool,
692 trailing_hardbreak: bool) -> io::Result<()> {
693 let mut count = 0;
694 for attr in attrs {
695 if attr.style == kind {
696 self.print_attribute_inline(attr, is_inline)?;
697 if is_inline {
698 self.nbsp()?;
699 }
700 count += 1;
701 }
702 }
703 if count > 0 && trailing_hardbreak && !is_inline {
704 self.hardbreak_if_not_bol()?;
705 }
706 Ok(())
707 }
708
709 fn print_attribute(&mut self, attr: &ast::Attribute) -> io::Result<()> {
710 self.print_attribute_inline(attr, false)
711 }
712
713 fn print_attribute_inline(&mut self, attr: &ast::Attribute,
714 is_inline: bool) -> io::Result<()> {
715 if !is_inline {
716 self.hardbreak_if_not_bol()?;
717 }
718 self.maybe_print_comment(attr.span.lo())?;
719 if attr.is_sugared_doc {
720 self.writer().word(&attr.value_str().unwrap().as_str())?;
721 self.writer().hardbreak()
722 } else {
723 match attr.style {
724 ast::AttrStyle::Inner => self.writer().word("#![")?,
725 ast::AttrStyle::Outer => self.writer().word("#[")?,
726 }
727 if let Some(mi) = attr.meta() {
728 self.print_meta_item(&mi)?
729 } else {
730 for (i, segment) in attr.path.segments.iter().enumerate() {
731 if i > 0 {
732 self.writer().word("::")?
733 }
734 if segment.identifier.name != keywords::CrateRoot.name() &&
735 segment.identifier.name != keywords::DollarCrate.name() {
736 self.writer().word(&segment.identifier.name.as_str())?;
737 }
738 }
739 self.writer().space()?;
740 self.print_tts(attr.tokens.clone())?;
741 }
742 self.writer().word("]")
743 }
744 }
745
746 fn print_meta_list_item(&mut self, item: &ast::NestedMetaItem) -> io::Result<()> {
747 match item.node {
748 ast::NestedMetaItemKind::MetaItem(ref mi) => {
749 self.print_meta_item(mi)
750 },
751 ast::NestedMetaItemKind::Literal(ref lit) => {
752 self.print_literal(lit)
753 }
754 }
755 }
756
757 fn print_meta_item(&mut self, item: &ast::MetaItem) -> io::Result<()> {
758 self.ibox(INDENT_UNIT)?;
759 match item.node {
760 ast::MetaItemKind::Word => {
761 self.writer().word(&item.name.as_str())?;
762 }
763 ast::MetaItemKind::NameValue(ref value) => {
764 self.word_space(&item.name.as_str())?;
765 self.word_space("=")?;
766 self.print_literal(value)?;
767 }
768 ast::MetaItemKind::List(ref items) => {
769 self.writer().word(&item.name.as_str())?;
770 self.popen()?;
771 self.commasep(Consistent,
772 &items[..],
773 |s, i| s.print_meta_list_item(i))?;
774 self.pclose()?;
775 }
776 }
777 self.end()
778 }
779
780 /// This doesn't deserve to be called "pretty" printing, but it should be
781 /// meaning-preserving. A quick hack that might help would be to look at the
782 /// spans embedded in the TTs to decide where to put spaces and newlines.
783 /// But it'd be better to parse these according to the grammar of the
784 /// appropriate macro, transcribe back into the grammar we just parsed from,
785 /// and then pretty-print the resulting AST nodes (so, e.g., we print
786 /// expression arguments as expressions). It can be done! I think.
787 fn print_tt(&mut self, tt: tokenstream::TokenTree) -> io::Result<()> {
788 match tt {
789 TokenTree::Token(_, ref tk) => {
790 self.writer().word(&token_to_string(tk))?;
791 match *tk {
792 parse::token::DocComment(..) => {
793 self.writer().hardbreak()
794 }
795 _ => Ok(())
796 }
797 }
798 TokenTree::Delimited(_, ref delimed) => {
799 self.writer().word(&token_to_string(&delimed.open_token()))?;
800 self.writer().space()?;
801 self.print_tts(delimed.stream())?;
802 self.writer().space()?;
803 self.writer().word(&token_to_string(&delimed.close_token()))
804 },
805 }
806 }
807
808 fn print_tts(&mut self, tts: tokenstream::TokenStream) -> io::Result<()> {
809 self.ibox(0)?;
810 for (i, tt) in tts.into_trees().enumerate() {
811 if i != 0 {
812 self.writer().space()?;
813 }
814 self.print_tt(tt)?;
815 }
816 self.end()
817 }
818
819 fn space_if_not_bol(&mut self) -> io::Result<()> {
820 if !self.is_bol() { self.writer().space()?; }
821 Ok(())
822 }
823
824 fn nbsp(&mut self) -> io::Result<()> { self.writer().word(" ") }
825 }
826
827 impl<'a> PrintState<'a> for State<'a> {
828 fn writer(&mut self) -> &mut pp::Printer<'a> {
829 &mut self.s
830 }
831
832 fn boxes(&mut self) -> &mut Vec<pp::Breaks> {
833 &mut self.boxes
834 }
835
836 fn comments(&mut self) -> &mut Option<Vec<comments::Comment>> {
837 &mut self.comments
838 }
839
840 fn cur_cmnt(&mut self) -> &mut usize {
841 &mut self.cur_cmnt
842 }
843
844 fn cur_lit(&mut self) -> Option<&comments::Literal> {
845 self.literals.peek()
846 }
847
848 fn bump_lit(&mut self) -> Option<comments::Literal> {
849 self.literals.next()
850 }
851 }
852
853 impl<'a> State<'a> {
854 pub fn cbox(&mut self, u: usize) -> io::Result<()> {
855 self.boxes.push(pp::Breaks::Consistent);
856 self.s.cbox(u)
857 }
858
859 pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> {
860 self.s.word(w)?;
861 self.nbsp()
862 }
863
864 pub fn head(&mut self, w: &str) -> io::Result<()> {
865 // outer-box is consistent
866 self.cbox(INDENT_UNIT)?;
867 // head-box is inconsistent
868 self.ibox(w.len() + 1)?;
869 // keyword that starts the head
870 if !w.is_empty() {
871 self.word_nbsp(w)?;
872 }
873 Ok(())
874 }
875
876 pub fn bopen(&mut self) -> io::Result<()> {
877 self.s.word("{")?;
878 self.end() // close the head-box
879 }
880
881 pub fn bclose_(&mut self, span: syntax_pos::Span,
882 indented: usize) -> io::Result<()> {
883 self.bclose_maybe_open(span, indented, true)
884 }
885 pub fn bclose_maybe_open(&mut self, span: syntax_pos::Span,
886 indented: usize, close_box: bool) -> io::Result<()> {
887 self.maybe_print_comment(span.hi())?;
888 self.break_offset_if_not_bol(1, -(indented as isize))?;
889 self.s.word("}")?;
890 if close_box {
891 self.end()?; // close the outer-box
892 }
893 Ok(())
894 }
895 pub fn bclose(&mut self, span: syntax_pos::Span) -> io::Result<()> {
896 self.bclose_(span, INDENT_UNIT)
897 }
898
899 pub fn in_cbox(&self) -> bool {
900 match self.boxes.last() {
901 Some(&last_box) => last_box == pp::Breaks::Consistent,
902 None => false
903 }
904 }
905
906 pub fn break_offset_if_not_bol(&mut self, n: usize,
907 off: isize) -> io::Result<()> {
908 if !self.is_bol() {
909 self.s.break_offset(n, off)
910 } else {
911 if off != 0 && self.s.last_token().is_hardbreak_tok() {
912 // We do something pretty sketchy here: tuck the nonzero
913 // offset-adjustment we were going to deposit along with the
914 // break into the previous hardbreak.
915 self.s.replace_last_token(pp::Printer::hardbreak_tok_offset(off));
916 }
917 Ok(())
918 }
919 }
920
921 // Synthesizes a comment that was not textually present in the original source
922 // file.
923 pub fn synth_comment(&mut self, text: String) -> io::Result<()> {
924 self.s.word("/*")?;
925 self.s.space()?;
926 self.s.word(&text[..])?;
927 self.s.space()?;
928 self.s.word("*/")
929 }
930
931
932
933 pub fn commasep_cmnt<T, F, G>(&mut self,
934 b: Breaks,
935 elts: &[T],
936 mut op: F,
937 mut get_span: G) -> io::Result<()> where
938 F: FnMut(&mut State, &T) -> io::Result<()>,
939 G: FnMut(&T) -> syntax_pos::Span,
940 {
941 self.rbox(0, b)?;
942 let len = elts.len();
943 let mut i = 0;
944 for elt in elts {
945 self.maybe_print_comment(get_span(elt).hi())?;
946 op(self, elt)?;
947 i += 1;
948 if i < len {
949 self.s.word(",")?;
950 self.maybe_print_trailing_comment(get_span(elt),
951 Some(get_span(&elts[i]).hi()))?;
952 self.space_if_not_bol()?;
953 }
954 }
955 self.end()
956 }
957
958 pub fn commasep_exprs(&mut self, b: Breaks,
959 exprs: &[P<ast::Expr>]) -> io::Result<()> {
960 self.commasep_cmnt(b, exprs, |s, e| s.print_expr(e), |e| e.span)
961 }
962
963 pub fn print_mod(&mut self, _mod: &ast::Mod,
964 attrs: &[ast::Attribute]) -> io::Result<()> {
965 self.print_inner_attributes(attrs)?;
966 for item in &_mod.items {
967 self.print_item(item)?;
968 }
969 Ok(())
970 }
971
972 pub fn print_foreign_mod(&mut self, nmod: &ast::ForeignMod,
973 attrs: &[ast::Attribute]) -> io::Result<()> {
974 self.print_inner_attributes(attrs)?;
975 for item in &nmod.items {
976 self.print_foreign_item(item)?;
977 }
978 Ok(())
979 }
980
981 pub fn print_opt_lifetime(&mut self,
982 lifetime: &Option<ast::Lifetime>) -> io::Result<()> {
983 if let Some(l) = *lifetime {
984 self.print_lifetime(&l)?;
985 self.nbsp()?;
986 }
987 Ok(())
988 }
989
990 pub fn print_type(&mut self, ty: &ast::Ty) -> io::Result<()> {
991 self.maybe_print_comment(ty.span.lo())?;
992 self.ibox(0)?;
993 match ty.node {
994 ast::TyKind::Slice(ref ty) => {
995 self.s.word("[")?;
996 self.print_type(ty)?;
997 self.s.word("]")?;
998 }
999 ast::TyKind::Ptr(ref mt) => {
1000 self.s.word("*")?;
1001 match mt.mutbl {
1002 ast::Mutability::Mutable => self.word_nbsp("mut")?,
1003 ast::Mutability::Immutable => self.word_nbsp("const")?,
1004 }
1005 self.print_type(&mt.ty)?;
1006 }
1007 ast::TyKind::Rptr(ref lifetime, ref mt) => {
1008 self.s.word("&")?;
1009 self.print_opt_lifetime(lifetime)?;
1010 self.print_mt(mt)?;
1011 }
1012 ast::TyKind::Never => {
1013 self.s.word("!")?;
1014 },
1015 ast::TyKind::Tup(ref elts) => {
1016 self.popen()?;
1017 self.commasep(Inconsistent, &elts[..],
1018 |s, ty| s.print_type(ty))?;
1019 if elts.len() == 1 {
1020 self.s.word(",")?;
1021 }
1022 self.pclose()?;
1023 }
1024 ast::TyKind::Paren(ref typ) => {
1025 self.popen()?;
1026 self.print_type(typ)?;
1027 self.pclose()?;
1028 }
1029 ast::TyKind::BareFn(ref f) => {
1030 let generics = ast::Generics {
1031 lifetimes: f.lifetimes.clone(),
1032 ty_params: Vec::new(),
1033 where_clause: ast::WhereClause {
1034 id: ast::DUMMY_NODE_ID,
1035 predicates: Vec::new(),
1036 span: syntax_pos::DUMMY_SP,
1037 },
1038 span: syntax_pos::DUMMY_SP,
1039 };
1040 self.print_ty_fn(f.abi,
1041 f.unsafety,
1042 &f.decl,
1043 None,
1044 &generics)?;
1045 }
1046 ast::TyKind::Path(None, ref path) => {
1047 self.print_path(path, false, 0, false)?;
1048 }
1049 ast::TyKind::Path(Some(ref qself), ref path) => {
1050 self.print_qpath(path, qself, false)?
1051 }
1052 ast::TyKind::TraitObject(ref bounds) => {
1053 self.print_bounds("", &bounds[..])?;
1054 }
1055 ast::TyKind::ImplTrait(ref bounds) => {
1056 self.print_bounds("impl ", &bounds[..])?;
1057 }
1058 ast::TyKind::Array(ref ty, ref v) => {
1059 self.s.word("[")?;
1060 self.print_type(ty)?;
1061 self.s.word("; ")?;
1062 self.print_expr(v)?;
1063 self.s.word("]")?;
1064 }
1065 ast::TyKind::Typeof(ref e) => {
1066 self.s.word("typeof(")?;
1067 self.print_expr(e)?;
1068 self.s.word(")")?;
1069 }
1070 ast::TyKind::Infer => {
1071 self.s.word("_")?;
1072 }
1073 ast::TyKind::Err => {
1074 self.s.word("?")?;
1075 }
1076 ast::TyKind::ImplicitSelf => {
1077 self.s.word("Self")?;
1078 }
1079 ast::TyKind::Mac(ref m) => {
1080 self.print_mac(m, token::Paren)?;
1081 }
1082 }
1083 self.end()
1084 }
1085
1086 pub fn print_foreign_item(&mut self,
1087 item: &ast::ForeignItem) -> io::Result<()> {
1088 self.hardbreak_if_not_bol()?;
1089 self.maybe_print_comment(item.span.lo())?;
1090 self.print_outer_attributes(&item.attrs)?;
1091 match item.node {
1092 ast::ForeignItemKind::Fn(ref decl, ref generics) => {
1093 self.head("")?;
1094 self.print_fn(decl, ast::Unsafety::Normal,
1095 ast::Constness::NotConst,
1096 Abi::Rust, Some(item.ident),
1097 generics, &item.vis)?;
1098 self.end()?; // end head-ibox
1099 self.s.word(";")?;
1100 self.end() // end the outer fn box
1101 }
1102 ast::ForeignItemKind::Static(ref t, m) => {
1103 self.head(&visibility_qualified(&item.vis, "static"))?;
1104 if m {
1105 self.word_space("mut")?;
1106 }
1107 self.print_ident(item.ident)?;
1108 self.word_space(":")?;
1109 self.print_type(t)?;
1110 self.s.word(";")?;
1111 self.end()?; // end the head-ibox
1112 self.end() // end the outer cbox
1113 }
1114 }
1115 }
1116
1117 fn print_associated_const(&mut self,
1118 ident: ast::Ident,
1119 ty: &ast::Ty,
1120 default: Option<&ast::Expr>,
1121 vis: &ast::Visibility)
1122 -> io::Result<()>
1123 {
1124 self.s.word(&visibility_qualified(vis, ""))?;
1125 self.word_space("const")?;
1126 self.print_ident(ident)?;
1127 self.word_space(":")?;
1128 self.print_type(ty)?;
1129 if let Some(expr) = default {
1130 self.s.space()?;
1131 self.word_space("=")?;
1132 self.print_expr(expr)?;
1133 }
1134 self.s.word(";")
1135 }
1136
1137 fn print_associated_type(&mut self,
1138 ident: ast::Ident,
1139 bounds: Option<&ast::TyParamBounds>,
1140 ty: Option<&ast::Ty>)
1141 -> io::Result<()> {
1142 self.word_space("type")?;
1143 self.print_ident(ident)?;
1144 if let Some(bounds) = bounds {
1145 self.print_bounds(":", bounds)?;
1146 }
1147 if let Some(ty) = ty {
1148 self.s.space()?;
1149 self.word_space("=")?;
1150 self.print_type(ty)?;
1151 }
1152 self.s.word(";")
1153 }
1154
1155 /// Pretty-print an item
1156 pub fn print_item(&mut self, item: &ast::Item) -> io::Result<()> {
1157 self.hardbreak_if_not_bol()?;
1158 self.maybe_print_comment(item.span.lo())?;
1159 self.print_outer_attributes(&item.attrs)?;
1160 self.ann.pre(self, NodeItem(item))?;
1161 match item.node {
1162 ast::ItemKind::ExternCrate(ref optional_path) => {
1163 self.head(&visibility_qualified(&item.vis, "extern crate"))?;
1164 if let Some(p) = *optional_path {
1165 let val = p.as_str();
1166 if val.contains('-') {
1167 self.print_string(&val, ast::StrStyle::Cooked)?;
1168 } else {
1169 self.print_name(p)?;
1170 }
1171 self.s.space()?;
1172 self.s.word("as")?;
1173 self.s.space()?;
1174 }
1175 self.print_ident(item.ident)?;
1176 self.s.word(";")?;
1177 self.end()?; // end inner head-block
1178 self.end()?; // end outer head-block
1179 }
1180 ast::ItemKind::Use(ref vp) => {
1181 self.head(&visibility_qualified(&item.vis, "use"))?;
1182 self.print_view_path(vp)?;
1183 self.s.word(";")?;
1184 self.end()?; // end inner head-block
1185 self.end()?; // end outer head-block
1186 }
1187 ast::ItemKind::Static(ref ty, m, ref expr) => {
1188 self.head(&visibility_qualified(&item.vis, "static"))?;
1189 if m == ast::Mutability::Mutable {
1190 self.word_space("mut")?;
1191 }
1192 self.print_ident(item.ident)?;
1193 self.word_space(":")?;
1194 self.print_type(ty)?;
1195 self.s.space()?;
1196 self.end()?; // end the head-ibox
1197
1198 self.word_space("=")?;
1199 self.print_expr(expr)?;
1200 self.s.word(";")?;
1201 self.end()?; // end the outer cbox
1202 }
1203 ast::ItemKind::Const(ref ty, ref expr) => {
1204 self.head(&visibility_qualified(&item.vis, "const"))?;
1205 self.print_ident(item.ident)?;
1206 self.word_space(":")?;
1207 self.print_type(ty)?;
1208 self.s.space()?;
1209 self.end()?; // end the head-ibox
1210
1211 self.word_space("=")?;
1212 self.print_expr(expr)?;
1213 self.s.word(";")?;
1214 self.end()?; // end the outer cbox
1215 }
1216 ast::ItemKind::Fn(ref decl, unsafety, constness, abi, ref typarams, ref body) => {
1217 self.head("")?;
1218 self.print_fn(
1219 decl,
1220 unsafety,
1221 constness.node,
1222 abi,
1223 Some(item.ident),
1224 typarams,
1225 &item.vis
1226 )?;
1227 self.s.word(" ")?;
1228 self.print_block_with_attrs(body, &item.attrs)?;
1229 }
1230 ast::ItemKind::Mod(ref _mod) => {
1231 self.head(&visibility_qualified(&item.vis, "mod"))?;
1232 self.print_ident(item.ident)?;
1233 self.nbsp()?;
1234 self.bopen()?;
1235 self.print_mod(_mod, &item.attrs)?;
1236 self.bclose(item.span)?;
1237 }
1238 ast::ItemKind::ForeignMod(ref nmod) => {
1239 self.head("extern")?;
1240 self.word_nbsp(&nmod.abi.to_string())?;
1241 self.bopen()?;
1242 self.print_foreign_mod(nmod, &item.attrs)?;
1243 self.bclose(item.span)?;
1244 }
1245 ast::ItemKind::GlobalAsm(ref ga) => {
1246 self.head(&visibility_qualified(&item.vis, "global_asm!"))?;
1247 self.s.word(&ga.asm.as_str())?;
1248 self.end()?;
1249 }
1250 ast::ItemKind::Ty(ref ty, ref params) => {
1251 self.ibox(INDENT_UNIT)?;
1252 self.ibox(0)?;
1253 self.word_nbsp(&visibility_qualified(&item.vis, "type"))?;
1254 self.print_ident(item.ident)?;
1255 self.print_generics(params)?;
1256 self.end()?; // end the inner ibox
1257
1258 self.print_where_clause(&params.where_clause)?;
1259 self.s.space()?;
1260 self.word_space("=")?;
1261 self.print_type(ty)?;
1262 self.s.word(";")?;
1263 self.end()?; // end the outer ibox
1264 }
1265 ast::ItemKind::Enum(ref enum_definition, ref params) => {
1266 self.print_enum_def(
1267 enum_definition,
1268 params,
1269 item.ident,
1270 item.span,
1271 &item.vis
1272 )?;
1273 }
1274 ast::ItemKind::Struct(ref struct_def, ref generics) => {
1275 self.head(&visibility_qualified(&item.vis, "struct"))?;
1276 self.print_struct(struct_def, generics, item.ident, item.span, true)?;
1277 }
1278 ast::ItemKind::Union(ref struct_def, ref generics) => {
1279 self.head(&visibility_qualified(&item.vis, "union"))?;
1280 self.print_struct(struct_def, generics, item.ident, item.span, true)?;
1281 }
1282 ast::ItemKind::DefaultImpl(unsafety, ref trait_ref) => {
1283 self.head("")?;
1284 self.print_visibility(&item.vis)?;
1285 self.print_unsafety(unsafety)?;
1286 self.word_nbsp("impl")?;
1287 self.print_trait_ref(trait_ref)?;
1288 self.s.space()?;
1289 self.word_space("for")?;
1290 self.word_space("..")?;
1291 self.bopen()?;
1292 self.bclose(item.span)?;
1293 }
1294 ast::ItemKind::Impl(unsafety,
1295 polarity,
1296 defaultness,
1297 ref generics,
1298 ref opt_trait,
1299 ref ty,
1300 ref impl_items) => {
1301 self.head("")?;
1302 self.print_visibility(&item.vis)?;
1303 self.print_defaultness(defaultness)?;
1304 self.print_unsafety(unsafety)?;
1305 self.word_nbsp("impl")?;
1306
1307 if generics.is_parameterized() {
1308 self.print_generics(generics)?;
1309 self.s.space()?;
1310 }
1311
1312 if polarity == ast::ImplPolarity::Negative {
1313 self.s.word("!")?;
1314 }
1315
1316 if let Some(ref t) = *opt_trait {
1317 self.print_trait_ref(t)?;
1318 self.s.space()?;
1319 self.word_space("for")?;
1320 }
1321
1322 self.print_type(ty)?;
1323 self.print_where_clause(&generics.where_clause)?;
1324
1325 self.s.space()?;
1326 self.bopen()?;
1327 self.print_inner_attributes(&item.attrs)?;
1328 for impl_item in impl_items {
1329 self.print_impl_item(impl_item)?;
1330 }
1331 self.bclose(item.span)?;
1332 }
1333 ast::ItemKind::Trait(unsafety, ref generics, ref bounds, ref trait_items) => {
1334 self.head("")?;
1335 self.print_visibility(&item.vis)?;
1336 self.print_unsafety(unsafety)?;
1337 self.word_nbsp("trait")?;
1338 self.print_ident(item.ident)?;
1339 self.print_generics(generics)?;
1340 let mut real_bounds = Vec::with_capacity(bounds.len());
1341 for b in bounds.iter() {
1342 if let TraitTyParamBound(ref ptr, ast::TraitBoundModifier::Maybe) = *b {
1343 self.s.space()?;
1344 self.word_space("for ?")?;
1345 self.print_trait_ref(&ptr.trait_ref)?;
1346 } else {
1347 real_bounds.push(b.clone());
1348 }
1349 }
1350 self.print_bounds(":", &real_bounds[..])?;
1351 self.print_where_clause(&generics.where_clause)?;
1352 self.s.word(" ")?;
1353 self.bopen()?;
1354 for trait_item in trait_items {
1355 self.print_trait_item(trait_item)?;
1356 }
1357 self.bclose(item.span)?;
1358 }
1359 ast::ItemKind::Mac(codemap::Spanned { ref node, .. }) => {
1360 self.print_path(&node.path, false, 0, false)?;
1361 self.s.word("! ")?;
1362 self.print_ident(item.ident)?;
1363 self.cbox(INDENT_UNIT)?;
1364 self.popen()?;
1365 self.print_tts(node.stream())?;
1366 self.pclose()?;
1367 self.s.word(";")?;
1368 self.end()?;
1369 }
1370 ast::ItemKind::MacroDef(ref tts) => {
1371 self.s.word("macro_rules! ")?;
1372 self.print_ident(item.ident)?;
1373 self.cbox(INDENT_UNIT)?;
1374 self.popen()?;
1375 self.print_tts(tts.stream())?;
1376 self.pclose()?;
1377 self.s.word(";")?;
1378 self.end()?;
1379 }
1380 }
1381 self.ann.post(self, NodeItem(item))
1382 }
1383
1384 fn print_trait_ref(&mut self, t: &ast::TraitRef) -> io::Result<()> {
1385 self.print_path(&t.path, false, 0, false)
1386 }
1387
1388 fn print_formal_lifetime_list(&mut self, lifetimes: &[ast::LifetimeDef]) -> io::Result<()> {
1389 if !lifetimes.is_empty() {
1390 self.s.word("for<")?;
1391 let mut comma = false;
1392 for lifetime_def in lifetimes {
1393 if comma {
1394 self.word_space(",")?
1395 }
1396 self.print_outer_attributes_inline(&lifetime_def.attrs)?;
1397 self.print_lifetime_bounds(&lifetime_def.lifetime, &lifetime_def.bounds)?;
1398 comma = true;
1399 }
1400 self.s.word(">")?;
1401 }
1402 Ok(())
1403 }
1404
1405 fn print_poly_trait_ref(&mut self, t: &ast::PolyTraitRef) -> io::Result<()> {
1406 self.print_formal_lifetime_list(&t.bound_lifetimes)?;
1407 self.print_trait_ref(&t.trait_ref)
1408 }
1409
1410 pub fn print_enum_def(&mut self, enum_definition: &ast::EnumDef,
1411 generics: &ast::Generics, ident: ast::Ident,
1412 span: syntax_pos::Span,
1413 visibility: &ast::Visibility) -> io::Result<()> {
1414 self.head(&visibility_qualified(visibility, "enum"))?;
1415 self.print_ident(ident)?;
1416 self.print_generics(generics)?;
1417 self.print_where_clause(&generics.where_clause)?;
1418 self.s.space()?;
1419 self.print_variants(&enum_definition.variants, span)
1420 }
1421
1422 pub fn print_variants(&mut self,
1423 variants: &[ast::Variant],
1424 span: syntax_pos::Span) -> io::Result<()> {
1425 self.bopen()?;
1426 for v in variants {
1427 self.space_if_not_bol()?;
1428 self.maybe_print_comment(v.span.lo())?;
1429 self.print_outer_attributes(&v.node.attrs)?;
1430 self.ibox(INDENT_UNIT)?;
1431 self.print_variant(v)?;
1432 self.s.word(",")?;
1433 self.end()?;
1434 self.maybe_print_trailing_comment(v.span, None)?;
1435 }
1436 self.bclose(span)
1437 }
1438
1439 pub fn print_visibility(&mut self, vis: &ast::Visibility) -> io::Result<()> {
1440 match *vis {
1441 ast::Visibility::Public => self.word_nbsp("pub"),
1442 ast::Visibility::Crate(_) => self.word_nbsp("pub(crate)"),
1443 ast::Visibility::Restricted { ref path, .. } => {
1444 let path = to_string(|s| s.print_path(path, false, 0, true));
1445 if path == "self" || path == "super" {
1446 self.word_nbsp(&format!("pub({})", path))
1447 } else {
1448 self.word_nbsp(&format!("pub(in {})", path))
1449 }
1450 }
1451 ast::Visibility::Inherited => Ok(())
1452 }
1453 }
1454
1455 pub fn print_defaultness(&mut self, defatulness: ast::Defaultness) -> io::Result<()> {
1456 if let ast::Defaultness::Default = defatulness {
1457 try!(self.word_nbsp("default"));
1458 }
1459 Ok(())
1460 }
1461
1462 pub fn print_struct(&mut self,
1463 struct_def: &ast::VariantData,
1464 generics: &ast::Generics,
1465 ident: ast::Ident,
1466 span: syntax_pos::Span,
1467 print_finalizer: bool) -> io::Result<()> {
1468 self.print_ident(ident)?;
1469 self.print_generics(generics)?;
1470 if !struct_def.is_struct() {
1471 if struct_def.is_tuple() {
1472 self.popen()?;
1473 self.commasep(
1474 Inconsistent, struct_def.fields(),
1475 |s, field| {
1476 s.maybe_print_comment(field.span.lo())?;
1477 s.print_outer_attributes(&field.attrs)?;
1478 s.print_visibility(&field.vis)?;
1479 s.print_type(&field.ty)
1480 }
1481 )?;
1482 self.pclose()?;
1483 }
1484 self.print_where_clause(&generics.where_clause)?;
1485 if print_finalizer {
1486 self.s.word(";")?;
1487 }
1488 self.end()?;
1489 self.end() // close the outer-box
1490 } else {
1491 self.print_where_clause(&generics.where_clause)?;
1492 self.nbsp()?;
1493 self.bopen()?;
1494 self.hardbreak_if_not_bol()?;
1495
1496 for field in struct_def.fields() {
1497 self.hardbreak_if_not_bol()?;
1498 self.maybe_print_comment(field.span.lo())?;
1499 self.print_outer_attributes(&field.attrs)?;
1500 self.print_visibility(&field.vis)?;
1501 self.print_ident(field.ident.unwrap())?;
1502 self.word_nbsp(":")?;
1503 self.print_type(&field.ty)?;
1504 self.s.word(",")?;
1505 }
1506
1507 self.bclose(span)
1508 }
1509 }
1510
1511 pub fn print_variant(&mut self, v: &ast::Variant) -> io::Result<()> {
1512 self.head("")?;
1513 let generics = ast::Generics::default();
1514 self.print_struct(&v.node.data, &generics, v.node.name, v.span, false)?;
1515 match v.node.disr_expr {
1516 Some(ref d) => {
1517 self.s.space()?;
1518 self.word_space("=")?;
1519 self.print_expr(d)
1520 }
1521 _ => Ok(())
1522 }
1523 }
1524
1525 pub fn print_method_sig(&mut self,
1526 ident: ast::Ident,
1527 m: &ast::MethodSig,
1528 vis: &ast::Visibility)
1529 -> io::Result<()> {
1530 self.print_fn(&m.decl,
1531 m.unsafety,
1532 m.constness.node,
1533 m.abi,
1534 Some(ident),
1535 &m.generics,
1536 vis)
1537 }
1538
1539 pub fn print_trait_item(&mut self, ti: &ast::TraitItem)
1540 -> io::Result<()> {
1541 self.ann.pre(self, NodeSubItem(ti.id))?;
1542 self.hardbreak_if_not_bol()?;
1543 self.maybe_print_comment(ti.span.lo())?;
1544 self.print_outer_attributes(&ti.attrs)?;
1545 match ti.node {
1546 ast::TraitItemKind::Const(ref ty, ref default) => {
1547 self.print_associated_const(ti.ident, ty,
1548 default.as_ref().map(|expr| &**expr),
1549 &ast::Visibility::Inherited)?;
1550 }
1551 ast::TraitItemKind::Method(ref sig, ref body) => {
1552 if body.is_some() {
1553 self.head("")?;
1554 }
1555 self.print_method_sig(ti.ident, sig, &ast::Visibility::Inherited)?;
1556 if let Some(ref body) = *body {
1557 self.nbsp()?;
1558 self.print_block_with_attrs(body, &ti.attrs)?;
1559 } else {
1560 self.s.word(";")?;
1561 }
1562 }
1563 ast::TraitItemKind::Type(ref bounds, ref default) => {
1564 self.print_associated_type(ti.ident, Some(bounds),
1565 default.as_ref().map(|ty| &**ty))?;
1566 }
1567 ast::TraitItemKind::Macro(codemap::Spanned { ref node, .. }) => {
1568 // code copied from ItemKind::Mac:
1569 self.print_path(&node.path, false, 0, false)?;
1570 self.s.word("! ")?;
1571 self.cbox(INDENT_UNIT)?;
1572 self.popen()?;
1573 self.print_tts(node.stream())?;
1574 self.pclose()?;
1575 self.s.word(";")?;
1576 self.end()?
1577 }
1578 }
1579 self.ann.post(self, NodeSubItem(ti.id))
1580 }
1581
1582 pub fn print_impl_item(&mut self, ii: &ast::ImplItem) -> io::Result<()> {
1583 self.ann.pre(self, NodeSubItem(ii.id))?;
1584 self.hardbreak_if_not_bol()?;
1585 self.maybe_print_comment(ii.span.lo())?;
1586 self.print_outer_attributes(&ii.attrs)?;
1587 self.print_defaultness(ii.defaultness)?;
1588 match ii.node {
1589 ast::ImplItemKind::Const(ref ty, ref expr) => {
1590 self.print_associated_const(ii.ident, ty, Some(expr), &ii.vis)?;
1591 }
1592 ast::ImplItemKind::Method(ref sig, ref body) => {
1593 self.head("")?;
1594 self.print_method_sig(ii.ident, sig, &ii.vis)?;
1595 self.nbsp()?;
1596 self.print_block_with_attrs(body, &ii.attrs)?;
1597 }
1598 ast::ImplItemKind::Type(ref ty) => {
1599 self.print_associated_type(ii.ident, None, Some(ty))?;
1600 }
1601 ast::ImplItemKind::Macro(codemap::Spanned { ref node, .. }) => {
1602 // code copied from ItemKind::Mac:
1603 self.print_path(&node.path, false, 0, false)?;
1604 self.s.word("! ")?;
1605 self.cbox(INDENT_UNIT)?;
1606 self.popen()?;
1607 self.print_tts(node.stream())?;
1608 self.pclose()?;
1609 self.s.word(";")?;
1610 self.end()?
1611 }
1612 }
1613 self.ann.post(self, NodeSubItem(ii.id))
1614 }
1615
1616 pub fn print_stmt(&mut self, st: &ast::Stmt) -> io::Result<()> {
1617 self.maybe_print_comment(st.span.lo())?;
1618 match st.node {
1619 ast::StmtKind::Local(ref loc) => {
1620 self.print_outer_attributes(&loc.attrs)?;
1621 self.space_if_not_bol()?;
1622 self.ibox(INDENT_UNIT)?;
1623 self.word_nbsp("let")?;
1624
1625 self.ibox(INDENT_UNIT)?;
1626 self.print_local_decl(loc)?;
1627 self.end()?;
1628 if let Some(ref init) = loc.init {
1629 self.nbsp()?;
1630 self.word_space("=")?;
1631 self.print_expr(init)?;
1632 }
1633 self.s.word(";")?;
1634 self.end()?;
1635 }
1636 ast::StmtKind::Item(ref item) => self.print_item(item)?,
1637 ast::StmtKind::Expr(ref expr) => {
1638 self.space_if_not_bol()?;
1639 self.print_expr_outer_attr_style(expr, false)?;
1640 if parse::classify::expr_requires_semi_to_be_stmt(expr) {
1641 self.s.word(";")?;
1642 }
1643 }
1644 ast::StmtKind::Semi(ref expr) => {
1645 self.space_if_not_bol()?;
1646 self.print_expr_outer_attr_style(expr, false)?;
1647 self.s.word(";")?;
1648 }
1649 ast::StmtKind::Mac(ref mac) => {
1650 let (ref mac, style, ref attrs) = **mac;
1651 self.space_if_not_bol()?;
1652 self.print_outer_attributes(attrs)?;
1653 let delim = match style {
1654 ast::MacStmtStyle::Braces => token::Brace,
1655 _ => token::Paren
1656 };
1657 self.print_mac(mac, delim)?;
1658 if style == ast::MacStmtStyle::Semicolon {
1659 self.s.word(";")?;
1660 }
1661 }
1662 }
1663 self.maybe_print_trailing_comment(st.span, None)
1664 }
1665
1666 pub fn print_block(&mut self, blk: &ast::Block) -> io::Result<()> {
1667 self.print_block_with_attrs(blk, &[])
1668 }
1669
1670 pub fn print_block_unclosed(&mut self, blk: &ast::Block) -> io::Result<()> {
1671 self.print_block_unclosed_indent(blk, INDENT_UNIT)
1672 }
1673
1674 pub fn print_block_unclosed_with_attrs(&mut self, blk: &ast::Block,
1675 attrs: &[ast::Attribute])
1676 -> io::Result<()> {
1677 self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, false)
1678 }
1679
1680 pub fn print_block_unclosed_indent(&mut self, blk: &ast::Block,
1681 indented: usize) -> io::Result<()> {
1682 self.print_block_maybe_unclosed(blk, indented, &[], false)
1683 }
1684
1685 pub fn print_block_with_attrs(&mut self,
1686 blk: &ast::Block,
1687 attrs: &[ast::Attribute]) -> io::Result<()> {
1688 self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, true)
1689 }
1690
1691 pub fn print_block_maybe_unclosed(&mut self,
1692 blk: &ast::Block,
1693 indented: usize,
1694 attrs: &[ast::Attribute],
1695 close_box: bool) -> io::Result<()> {
1696 match blk.rules {
1697 BlockCheckMode::Unsafe(..) => self.word_space("unsafe")?,
1698 BlockCheckMode::Default => ()
1699 }
1700 self.maybe_print_comment(blk.span.lo())?;
1701 self.ann.pre(self, NodeBlock(blk))?;
1702 self.bopen()?;
1703
1704 self.print_inner_attributes(attrs)?;
1705
1706 for (i, st) in blk.stmts.iter().enumerate() {
1707 match st.node {
1708 ast::StmtKind::Expr(ref expr) if i == blk.stmts.len() - 1 => {
1709 self.maybe_print_comment(st.span.lo())?;
1710 self.space_if_not_bol()?;
1711 self.print_expr_outer_attr_style(expr, false)?;
1712 self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi()))?;
1713 }
1714 _ => self.print_stmt(st)?,
1715 }
1716 }
1717
1718 self.bclose_maybe_open(blk.span, indented, close_box)?;
1719 self.ann.post(self, NodeBlock(blk))
1720 }
1721
1722 fn print_else(&mut self, els: Option<&ast::Expr>) -> io::Result<()> {
1723 match els {
1724 Some(_else) => {
1725 match _else.node {
1726 // "another else-if"
1727 ast::ExprKind::If(ref i, ref then, ref e) => {
1728 self.cbox(INDENT_UNIT - 1)?;
1729 self.ibox(0)?;
1730 self.s.word(" else if ")?;
1731 self.print_expr_as_cond(i)?;
1732 self.s.space()?;
1733 self.print_block(then)?;
1734 self.print_else(e.as_ref().map(|e| &**e))
1735 }
1736 // "another else-if-let"
1737 ast::ExprKind::IfLet(ref pat, ref expr, ref then, ref e) => {
1738 self.cbox(INDENT_UNIT - 1)?;
1739 self.ibox(0)?;
1740 self.s.word(" else if let ")?;
1741 self.print_pat(pat)?;
1742 self.s.space()?;
1743 self.word_space("=")?;
1744 self.print_expr_as_cond(expr)?;
1745 self.s.space()?;
1746 self.print_block(then)?;
1747 self.print_else(e.as_ref().map(|e| &**e))
1748 }
1749 // "final else"
1750 ast::ExprKind::Block(ref b) => {
1751 self.cbox(INDENT_UNIT - 1)?;
1752 self.ibox(0)?;
1753 self.s.word(" else ")?;
1754 self.print_block(b)
1755 }
1756 // BLEAH, constraints would be great here
1757 _ => {
1758 panic!("print_if saw if with weird alternative");
1759 }
1760 }
1761 }
1762 _ => Ok(())
1763 }
1764 }
1765
1766 pub fn print_if(&mut self, test: &ast::Expr, blk: &ast::Block,
1767 elseopt: Option<&ast::Expr>) -> io::Result<()> {
1768 self.head("if")?;
1769 self.print_expr_as_cond(test)?;
1770 self.s.space()?;
1771 self.print_block(blk)?;
1772 self.print_else(elseopt)
1773 }
1774
1775 pub fn print_if_let(&mut self, pat: &ast::Pat, expr: &ast::Expr, blk: &ast::Block,
1776 elseopt: Option<&ast::Expr>) -> io::Result<()> {
1777 self.head("if let")?;
1778 self.print_pat(pat)?;
1779 self.s.space()?;
1780 self.word_space("=")?;
1781 self.print_expr_as_cond(expr)?;
1782 self.s.space()?;
1783 self.print_block(blk)?;
1784 self.print_else(elseopt)
1785 }
1786
1787 pub fn print_mac(&mut self, m: &ast::Mac, delim: token::DelimToken)
1788 -> io::Result<()> {
1789 self.print_path(&m.node.path, false, 0, false)?;
1790 self.s.word("!")?;
1791 match delim {
1792 token::Paren => self.popen()?,
1793 token::Bracket => self.s.word("[")?,
1794 token::Brace => {
1795 self.head("")?;
1796 self.bopen()?;
1797 }
1798 token::NoDelim => {}
1799 }
1800 self.print_tts(m.node.stream())?;
1801 match delim {
1802 token::Paren => self.pclose(),
1803 token::Bracket => self.s.word("]"),
1804 token::Brace => self.bclose(m.span),
1805 token::NoDelim => Ok(()),
1806 }
1807 }
1808
1809
1810 fn print_call_post(&mut self, args: &[P<ast::Expr>]) -> io::Result<()> {
1811 self.popen()?;
1812 self.commasep_exprs(Inconsistent, args)?;
1813 self.pclose()
1814 }
1815
1816 pub fn print_expr_maybe_paren(&mut self, expr: &ast::Expr, prec: i8) -> io::Result<()> {
1817 let needs_par = parser::expr_precedence(expr) < prec;
1818 if needs_par {
1819 self.popen()?;
1820 }
1821 self.print_expr(expr)?;
1822 if needs_par {
1823 self.pclose()?;
1824 }
1825 Ok(())
1826 }
1827
1828 /// Print an expr using syntax that's acceptable in a condition position, such as the `cond` in
1829 /// `if cond { ... }`.
1830 pub fn print_expr_as_cond(&mut self, expr: &ast::Expr) -> io::Result<()> {
1831 let needs_par = match expr.node {
1832 // These cases need parens due to the parse error observed in #26461: `if return {}`
1833 // parses as the erroneous construct `if (return {})`, not `if (return) {}`.
1834 ast::ExprKind::Closure(..) |
1835 ast::ExprKind::Ret(..) |
1836 ast::ExprKind::Break(..) => true,
1837
1838 _ => parser::contains_exterior_struct_lit(expr),
1839 };
1840
1841 if needs_par {
1842 self.popen()?;
1843 }
1844 self.print_expr(expr)?;
1845 if needs_par {
1846 self.pclose()?;
1847 }
1848 Ok(())
1849 }
1850
1851 fn print_expr_in_place(&mut self,
1852 place: &ast::Expr,
1853 expr: &ast::Expr) -> io::Result<()> {
1854 let prec = AssocOp::Inplace.precedence() as i8;
1855 self.print_expr_maybe_paren(place, prec + 1)?;
1856 self.s.space()?;
1857 self.word_space("<-")?;
1858 self.print_expr_maybe_paren(expr, prec)
1859 }
1860
1861 fn print_expr_vec(&mut self, exprs: &[P<ast::Expr>],
1862 attrs: &[Attribute]) -> io::Result<()> {
1863 self.ibox(INDENT_UNIT)?;
1864 self.s.word("[")?;
1865 self.print_inner_attributes_inline(attrs)?;
1866 self.commasep_exprs(Inconsistent, &exprs[..])?;
1867 self.s.word("]")?;
1868 self.end()
1869 }
1870
1871 fn print_expr_repeat(&mut self,
1872 element: &ast::Expr,
1873 count: &ast::Expr,
1874 attrs: &[Attribute]) -> io::Result<()> {
1875 self.ibox(INDENT_UNIT)?;
1876 self.s.word("[")?;
1877 self.print_inner_attributes_inline(attrs)?;
1878 self.print_expr(element)?;
1879 self.word_space(";")?;
1880 self.print_expr(count)?;
1881 self.s.word("]")?;
1882 self.end()
1883 }
1884
1885 fn print_expr_struct(&mut self,
1886 path: &ast::Path,
1887 fields: &[ast::Field],
1888 wth: &Option<P<ast::Expr>>,
1889 attrs: &[Attribute]) -> io::Result<()> {
1890 self.print_path(path, true, 0, false)?;
1891 self.s.word("{")?;
1892 self.print_inner_attributes_inline(attrs)?;
1893 self.commasep_cmnt(
1894 Consistent,
1895 &fields[..],
1896 |s, field| {
1897 s.ibox(INDENT_UNIT)?;
1898 if !field.is_shorthand {
1899 s.print_ident(field.ident.node)?;
1900 s.word_space(":")?;
1901 }
1902 s.print_expr(&field.expr)?;
1903 s.end()
1904 },
1905 |f| f.span)?;
1906 match *wth {
1907 Some(ref expr) => {
1908 self.ibox(INDENT_UNIT)?;
1909 if !fields.is_empty() {
1910 self.s.word(",")?;
1911 self.s.space()?;
1912 }
1913 self.s.word("..")?;
1914 self.print_expr(expr)?;
1915 self.end()?;
1916 }
1917 _ => if !fields.is_empty() {
1918 self.s.word(",")?
1919 }
1920 }
1921 self.s.word("}")?;
1922 Ok(())
1923 }
1924
1925 fn print_expr_tup(&mut self, exprs: &[P<ast::Expr>],
1926 attrs: &[Attribute]) -> io::Result<()> {
1927 self.popen()?;
1928 self.print_inner_attributes_inline(attrs)?;
1929 self.commasep_exprs(Inconsistent, &exprs[..])?;
1930 if exprs.len() == 1 {
1931 self.s.word(",")?;
1932 }
1933 self.pclose()
1934 }
1935
1936 fn print_expr_call(&mut self,
1937 func: &ast::Expr,
1938 args: &[P<ast::Expr>]) -> io::Result<()> {
1939 let prec =
1940 match func.node {
1941 ast::ExprKind::Field(..) |
1942 ast::ExprKind::TupField(..) => parser::PREC_FORCE_PAREN,
1943 _ => parser::PREC_POSTFIX,
1944 };
1945
1946 self.print_expr_maybe_paren(func, prec)?;
1947 self.print_call_post(args)
1948 }
1949
1950 fn print_expr_method_call(&mut self,
1951 segment: &ast::PathSegment,
1952 args: &[P<ast::Expr>]) -> io::Result<()> {
1953 let base_args = &args[1..];
1954 self.print_expr_maybe_paren(&args[0], parser::PREC_POSTFIX)?;
1955 self.s.word(".")?;
1956 self.print_ident(segment.identifier)?;
1957 if let Some(ref parameters) = segment.parameters {
1958 self.print_path_parameters(parameters, true)?;
1959 }
1960 self.print_call_post(base_args)
1961 }
1962
1963 fn print_expr_binary(&mut self,
1964 op: ast::BinOp,
1965 lhs: &ast::Expr,
1966 rhs: &ast::Expr) -> io::Result<()> {
1967 let assoc_op = AssocOp::from_ast_binop(op.node);
1968 let prec = assoc_op.precedence() as i8;
1969 let fixity = assoc_op.fixity();
1970
1971 let (left_prec, right_prec) = match fixity {
1972 Fixity::Left => (prec, prec + 1),
1973 Fixity::Right => (prec + 1, prec),
1974 Fixity::None => (prec + 1, prec + 1),
1975 };
1976
1977 self.print_expr_maybe_paren(lhs, left_prec)?;
1978 self.s.space()?;
1979 self.word_space(op.node.to_string())?;
1980 self.print_expr_maybe_paren(rhs, right_prec)
1981 }
1982
1983 fn print_expr_unary(&mut self,
1984 op: ast::UnOp,
1985 expr: &ast::Expr) -> io::Result<()> {
1986 self.s.word(ast::UnOp::to_string(op))?;
1987 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
1988 }
1989
1990 fn print_expr_addr_of(&mut self,
1991 mutability: ast::Mutability,
1992 expr: &ast::Expr) -> io::Result<()> {
1993 self.s.word("&")?;
1994 self.print_mutability(mutability)?;
1995 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
1996 }
1997
1998 pub fn print_expr(&mut self, expr: &ast::Expr) -> io::Result<()> {
1999 self.print_expr_outer_attr_style(expr, true)
2000 }
2001
2002 fn print_expr_outer_attr_style(&mut self,
2003 expr: &ast::Expr,
2004 is_inline: bool) -> io::Result<()> {
2005 self.maybe_print_comment(expr.span.lo())?;
2006
2007 let attrs = &expr.attrs;
2008 if is_inline {
2009 self.print_outer_attributes_inline(attrs)?;
2010 } else {
2011 self.print_outer_attributes(attrs)?;
2012 }
2013
2014 self.ibox(INDENT_UNIT)?;
2015 self.ann.pre(self, NodeExpr(expr))?;
2016 match expr.node {
2017 ast::ExprKind::Box(ref expr) => {
2018 self.word_space("box")?;
2019 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)?;
2020 }
2021 ast::ExprKind::InPlace(ref place, ref expr) => {
2022 self.print_expr_in_place(place, expr)?;
2023 }
2024 ast::ExprKind::Array(ref exprs) => {
2025 self.print_expr_vec(&exprs[..], attrs)?;
2026 }
2027 ast::ExprKind::Repeat(ref element, ref count) => {
2028 self.print_expr_repeat(element, count, attrs)?;
2029 }
2030 ast::ExprKind::Struct(ref path, ref fields, ref wth) => {
2031 self.print_expr_struct(path, &fields[..], wth, attrs)?;
2032 }
2033 ast::ExprKind::Tup(ref exprs) => {
2034 self.print_expr_tup(&exprs[..], attrs)?;
2035 }
2036 ast::ExprKind::Call(ref func, ref args) => {
2037 self.print_expr_call(func, &args[..])?;
2038 }
2039 ast::ExprKind::MethodCall(ref segment, ref args) => {
2040 self.print_expr_method_call(segment, &args[..])?;
2041 }
2042 ast::ExprKind::Binary(op, ref lhs, ref rhs) => {
2043 self.print_expr_binary(op, lhs, rhs)?;
2044 }
2045 ast::ExprKind::Unary(op, ref expr) => {
2046 self.print_expr_unary(op, expr)?;
2047 }
2048 ast::ExprKind::AddrOf(m, ref expr) => {
2049 self.print_expr_addr_of(m, expr)?;
2050 }
2051 ast::ExprKind::Lit(ref lit) => {
2052 self.print_literal(lit)?;
2053 }
2054 ast::ExprKind::Cast(ref expr, ref ty) => {
2055 let prec = AssocOp::As.precedence() as i8;
2056 self.print_expr_maybe_paren(expr, prec)?;
2057 self.s.space()?;
2058 self.word_space("as")?;
2059 self.print_type(ty)?;
2060 }
2061 ast::ExprKind::Type(ref expr, ref ty) => {
2062 let prec = AssocOp::Colon.precedence() as i8;
2063 self.print_expr_maybe_paren(expr, prec)?;
2064 self.word_space(":")?;
2065 self.print_type(ty)?;
2066 }
2067 ast::ExprKind::If(ref test, ref blk, ref elseopt) => {
2068 self.print_if(test, blk, elseopt.as_ref().map(|e| &**e))?;
2069 }
2070 ast::ExprKind::IfLet(ref pat, ref expr, ref blk, ref elseopt) => {
2071 self.print_if_let(pat, expr, blk, elseopt.as_ref().map(|e| &**e))?;
2072 }
2073 ast::ExprKind::While(ref test, ref blk, opt_ident) => {
2074 if let Some(ident) = opt_ident {
2075 self.print_ident(ident.node)?;
2076 self.word_space(":")?;
2077 }
2078 self.head("while")?;
2079 self.print_expr_as_cond(test)?;
2080 self.s.space()?;
2081 self.print_block_with_attrs(blk, attrs)?;
2082 }
2083 ast::ExprKind::WhileLet(ref pat, ref expr, ref blk, opt_ident) => {
2084 if let Some(ident) = opt_ident {
2085 self.print_ident(ident.node)?;
2086 self.word_space(":")?;
2087 }
2088 self.head("while let")?;
2089 self.print_pat(pat)?;
2090 self.s.space()?;
2091 self.word_space("=")?;
2092 self.print_expr_as_cond(expr)?;
2093 self.s.space()?;
2094 self.print_block_with_attrs(blk, attrs)?;
2095 }
2096 ast::ExprKind::ForLoop(ref pat, ref iter, ref blk, opt_ident) => {
2097 if let Some(ident) = opt_ident {
2098 self.print_ident(ident.node)?;
2099 self.word_space(":")?;
2100 }
2101 self.head("for")?;
2102 self.print_pat(pat)?;
2103 self.s.space()?;
2104 self.word_space("in")?;
2105 self.print_expr_as_cond(iter)?;
2106 self.s.space()?;
2107 self.print_block_with_attrs(blk, attrs)?;
2108 }
2109 ast::ExprKind::Loop(ref blk, opt_ident) => {
2110 if let Some(ident) = opt_ident {
2111 self.print_ident(ident.node)?;
2112 self.word_space(":")?;
2113 }
2114 self.head("loop")?;
2115 self.s.space()?;
2116 self.print_block_with_attrs(blk, attrs)?;
2117 }
2118 ast::ExprKind::Match(ref expr, ref arms) => {
2119 self.cbox(INDENT_UNIT)?;
2120 self.ibox(4)?;
2121 self.word_nbsp("match")?;
2122 self.print_expr_as_cond(expr)?;
2123 self.s.space()?;
2124 self.bopen()?;
2125 self.print_inner_attributes_no_trailing_hardbreak(attrs)?;
2126 for arm in arms {
2127 self.print_arm(arm)?;
2128 }
2129 self.bclose_(expr.span, INDENT_UNIT)?;
2130 }
2131 ast::ExprKind::Closure(capture_clause, ref decl, ref body, _) => {
2132 self.print_capture_clause(capture_clause)?;
2133
2134 self.print_fn_block_args(decl)?;
2135 self.s.space()?;
2136 self.print_expr(body)?;
2137 self.end()?; // need to close a box
2138
2139 // a box will be closed by print_expr, but we didn't want an overall
2140 // wrapper so we closed the corresponding opening. so create an
2141 // empty box to satisfy the close.
2142 self.ibox(0)?;
2143 }
2144 ast::ExprKind::Block(ref blk) => {
2145 // containing cbox, will be closed by print-block at }
2146 self.cbox(INDENT_UNIT)?;
2147 // head-box, will be closed by print-block after {
2148 self.ibox(0)?;
2149 self.print_block_with_attrs(blk, attrs)?;
2150 }
2151 ast::ExprKind::Assign(ref lhs, ref rhs) => {
2152 let prec = AssocOp::Assign.precedence() as i8;
2153 self.print_expr_maybe_paren(lhs, prec + 1)?;
2154 self.s.space()?;
2155 self.word_space("=")?;
2156 self.print_expr_maybe_paren(rhs, prec)?;
2157 }
2158 ast::ExprKind::AssignOp(op, ref lhs, ref rhs) => {
2159 let prec = AssocOp::Assign.precedence() as i8;
2160 self.print_expr_maybe_paren(lhs, prec + 1)?;
2161 self.s.space()?;
2162 self.s.word(op.node.to_string())?;
2163 self.word_space("=")?;
2164 self.print_expr_maybe_paren(rhs, prec)?;
2165 }
2166 ast::ExprKind::Field(ref expr, id) => {
2167 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
2168 self.s.word(".")?;
2169 self.print_ident(id.node)?;
2170 }
2171 ast::ExprKind::TupField(ref expr, id) => {
2172 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
2173 self.s.word(".")?;
2174 self.print_usize(id.node)?;
2175 }
2176 ast::ExprKind::Index(ref expr, ref index) => {
2177 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
2178 self.s.word("[")?;
2179 self.print_expr(index)?;
2180 self.s.word("]")?;
2181 }
2182 ast::ExprKind::Range(ref start, ref end, limits) => {
2183 // Special case for `Range`. `AssocOp` claims that `Range` has higher precedence
2184 // than `Assign`, but `x .. x = x` gives a parse error instead of `x .. (x = x)`.
2185 // Here we use a fake precedence value so that any child with lower precedence than
2186 // a "normal" binop gets parenthesized. (`LOr` is the lowest-precedence binop.)
2187 let fake_prec = AssocOp::LOr.precedence() as i8;
2188 if let Some(ref e) = *start {
2189 self.print_expr_maybe_paren(e, fake_prec)?;
2190 }
2191 if limits == ast::RangeLimits::HalfOpen {
2192 self.s.word("..")?;
2193 } else {
2194 self.s.word("...")?;
2195 }
2196 if let Some(ref e) = *end {
2197 self.print_expr_maybe_paren(e, fake_prec)?;
2198 }
2199 }
2200 ast::ExprKind::Path(None, ref path) => {
2201 self.print_path(path, true, 0, false)?
2202 }
2203 ast::ExprKind::Path(Some(ref qself), ref path) => {
2204 self.print_qpath(path, qself, true)?
2205 }
2206 ast::ExprKind::Break(opt_ident, ref opt_expr) => {
2207 self.s.word("break")?;
2208 self.s.space()?;
2209 if let Some(ident) = opt_ident {
2210 self.print_ident(ident.node)?;
2211 self.s.space()?;
2212 }
2213 if let Some(ref expr) = *opt_expr {
2214 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2215 self.s.space()?;
2216 }
2217 }
2218 ast::ExprKind::Continue(opt_ident) => {
2219 self.s.word("continue")?;
2220 self.s.space()?;
2221 if let Some(ident) = opt_ident {
2222 self.print_ident(ident.node)?;
2223 self.s.space()?
2224 }
2225 }
2226 ast::ExprKind::Ret(ref result) => {
2227 self.s.word("return")?;
2228 if let Some(ref expr) = *result {
2229 self.s.word(" ")?;
2230 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2231 }
2232 }
2233 ast::ExprKind::InlineAsm(ref a) => {
2234 self.s.word("asm!")?;
2235 self.popen()?;
2236 self.print_string(&a.asm.as_str(), a.asm_str_style)?;
2237 self.word_space(":")?;
2238
2239 self.commasep(Inconsistent, &a.outputs, |s, out| {
2240 let constraint = out.constraint.as_str();
2241 let mut ch = constraint.chars();
2242 match ch.next() {
2243 Some('=') if out.is_rw => {
2244 s.print_string(&format!("+{}", ch.as_str()),
2245 ast::StrStyle::Cooked)?
2246 }
2247 _ => s.print_string(&constraint, ast::StrStyle::Cooked)?
2248 }
2249 s.popen()?;
2250 s.print_expr(&out.expr)?;
2251 s.pclose()?;
2252 Ok(())
2253 })?;
2254 self.s.space()?;
2255 self.word_space(":")?;
2256
2257 self.commasep(Inconsistent, &a.inputs, |s, &(co, ref o)| {
2258 s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
2259 s.popen()?;
2260 s.print_expr(o)?;
2261 s.pclose()?;
2262 Ok(())
2263 })?;
2264 self.s.space()?;
2265 self.word_space(":")?;
2266
2267 self.commasep(Inconsistent, &a.clobbers,
2268 |s, co| {
2269 s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
2270 Ok(())
2271 })?;
2272
2273 let mut options = vec![];
2274 if a.volatile {
2275 options.push("volatile");
2276 }
2277 if a.alignstack {
2278 options.push("alignstack");
2279 }
2280 if a.dialect == ast::AsmDialect::Intel {
2281 options.push("intel");
2282 }
2283
2284 if !options.is_empty() {
2285 self.s.space()?;
2286 self.word_space(":")?;
2287 self.commasep(Inconsistent, &options,
2288 |s, &co| {
2289 s.print_string(co, ast::StrStyle::Cooked)?;
2290 Ok(())
2291 })?;
2292 }
2293
2294 self.pclose()?;
2295 }
2296 ast::ExprKind::Mac(ref m) => self.print_mac(m, token::Paren)?,
2297 ast::ExprKind::Paren(ref e) => {
2298 self.popen()?;
2299 self.print_inner_attributes_inline(attrs)?;
2300 self.print_expr(e)?;
2301 self.pclose()?;
2302 },
2303 ast::ExprKind::Yield(ref e) => {
2304 self.s.word("yield")?;
2305 match *e {
2306 Some(ref expr) => {
2307 self.s.space()?;
2308 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2309 }
2310 _ => ()
2311 }
2312 }
2313 ast::ExprKind::Try(ref e) => {
2314 self.print_expr_maybe_paren(e, parser::PREC_POSTFIX)?;
2315 self.s.word("?")?
2316 }
2317 ast::ExprKind::Catch(ref blk) => {
2318 self.head("do catch")?;
2319 self.s.space()?;
2320 self.print_block_with_attrs(blk, attrs)?
2321 }
2322 }
2323 self.ann.post(self, NodeExpr(expr))?;
2324 self.end()
2325 }
2326
2327 pub fn print_local_decl(&mut self, loc: &ast::Local) -> io::Result<()> {
2328 self.print_pat(&loc.pat)?;
2329 if let Some(ref ty) = loc.ty {
2330 self.word_space(":")?;
2331 self.print_type(ty)?;
2332 }
2333 Ok(())
2334 }
2335
2336 pub fn print_ident(&mut self, ident: ast::Ident) -> io::Result<()> {
2337 self.s.word(&ident.name.as_str())?;
2338 self.ann.post(self, NodeIdent(&ident))
2339 }
2340
2341 pub fn print_usize(&mut self, i: usize) -> io::Result<()> {
2342 self.s.word(&i.to_string())
2343 }
2344
2345 pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
2346 self.s.word(&name.as_str())?;
2347 self.ann.post(self, NodeName(&name))
2348 }
2349
2350 pub fn print_for_decl(&mut self, loc: &ast::Local,
2351 coll: &ast::Expr) -> io::Result<()> {
2352 self.print_local_decl(loc)?;
2353 self.s.space()?;
2354 self.word_space("in")?;
2355 self.print_expr(coll)
2356 }
2357
2358 fn print_path(&mut self,
2359 path: &ast::Path,
2360 colons_before_params: bool,
2361 depth: usize,
2362 defaults_to_global: bool)
2363 -> io::Result<()>
2364 {
2365 self.maybe_print_comment(path.span.lo())?;
2366
2367 let mut segments = path.segments[..path.segments.len()-depth].iter();
2368 if defaults_to_global && path.is_global() {
2369 segments.next();
2370 }
2371 for (i, segment) in segments.enumerate() {
2372 if i > 0 {
2373 self.s.word("::")?
2374 }
2375 self.print_path_segment(segment, colons_before_params)?;
2376 }
2377
2378 Ok(())
2379 }
2380
2381 fn print_path_segment(&mut self,
2382 segment: &ast::PathSegment,
2383 colons_before_params: bool)
2384 -> io::Result<()>
2385 {
2386 if segment.identifier.name != keywords::CrateRoot.name() &&
2387 segment.identifier.name != keywords::DollarCrate.name() {
2388 self.print_ident(segment.identifier)?;
2389 if let Some(ref parameters) = segment.parameters {
2390 self.print_path_parameters(parameters, colons_before_params)?;
2391 }
2392 }
2393 Ok(())
2394 }
2395
2396 fn print_qpath(&mut self,
2397 path: &ast::Path,
2398 qself: &ast::QSelf,
2399 colons_before_params: bool)
2400 -> io::Result<()>
2401 {
2402 self.s.word("<")?;
2403 self.print_type(&qself.ty)?;
2404 if qself.position > 0 {
2405 self.s.space()?;
2406 self.word_space("as")?;
2407 let depth = path.segments.len() - qself.position;
2408 self.print_path(path, false, depth, false)?;
2409 }
2410 self.s.word(">")?;
2411 self.s.word("::")?;
2412 let item_segment = path.segments.last().unwrap();
2413 self.print_ident(item_segment.identifier)?;
2414 match item_segment.parameters {
2415 Some(ref parameters) => self.print_path_parameters(parameters, colons_before_params),
2416 None => Ok(()),
2417 }
2418 }
2419
2420 fn print_path_parameters(&mut self,
2421 parameters: &ast::PathParameters,
2422 colons_before_params: bool)
2423 -> io::Result<()>
2424 {
2425 if colons_before_params {
2426 self.s.word("::")?
2427 }
2428
2429 match *parameters {
2430 ast::PathParameters::AngleBracketed(ref data) => {
2431 self.s.word("<")?;
2432
2433 let mut comma = false;
2434 for lifetime in &data.lifetimes {
2435 if comma {
2436 self.word_space(",")?
2437 }
2438 self.print_lifetime(lifetime)?;
2439 comma = true;
2440 }
2441
2442 if !data.types.is_empty() {
2443 if comma {
2444 self.word_space(",")?
2445 }
2446 self.commasep(
2447 Inconsistent,
2448 &data.types,
2449 |s, ty| s.print_type(ty))?;
2450 comma = true;
2451 }
2452
2453 for binding in data.bindings.iter() {
2454 if comma {
2455 self.word_space(",")?
2456 }
2457 self.print_ident(binding.ident)?;
2458 self.s.space()?;
2459 self.word_space("=")?;
2460 self.print_type(&binding.ty)?;
2461 comma = true;
2462 }
2463
2464 self.s.word(">")?
2465 }
2466
2467 ast::PathParameters::Parenthesized(ref data) => {
2468 self.s.word("(")?;
2469 self.commasep(
2470 Inconsistent,
2471 &data.inputs,
2472 |s, ty| s.print_type(ty))?;
2473 self.s.word(")")?;
2474
2475 if let Some(ref ty) = data.output {
2476 self.space_if_not_bol()?;
2477 self.word_space("->")?;
2478 self.print_type(ty)?;
2479 }
2480 }
2481 }
2482
2483 Ok(())
2484 }
2485
2486 pub fn print_pat(&mut self, pat: &ast::Pat) -> io::Result<()> {
2487 self.maybe_print_comment(pat.span.lo())?;
2488 self.ann.pre(self, NodePat(pat))?;
2489 /* Pat isn't normalized, but the beauty of it
2490 is that it doesn't matter */
2491 match pat.node {
2492 PatKind::Wild => self.s.word("_")?,
2493 PatKind::Ident(binding_mode, ref path1, ref sub) => {
2494 match binding_mode {
2495 ast::BindingMode::ByRef(mutbl) => {
2496 self.word_nbsp("ref")?;
2497 self.print_mutability(mutbl)?;
2498 }
2499 ast::BindingMode::ByValue(ast::Mutability::Immutable) => {}
2500 ast::BindingMode::ByValue(ast::Mutability::Mutable) => {
2501 self.word_nbsp("mut")?;
2502 }
2503 }
2504 self.print_ident(path1.node)?;
2505 if let Some(ref p) = *sub {
2506 self.s.word("@")?;
2507 self.print_pat(p)?;
2508 }
2509 }
2510 PatKind::TupleStruct(ref path, ref elts, ddpos) => {
2511 self.print_path(path, true, 0, false)?;
2512 self.popen()?;
2513 if let Some(ddpos) = ddpos {
2514 self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?;
2515 if ddpos != 0 {
2516 self.word_space(",")?;
2517 }
2518 self.s.word("..")?;
2519 if ddpos != elts.len() {
2520 self.s.word(",")?;
2521 self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?;
2522 }
2523 } else {
2524 self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?;
2525 }
2526 self.pclose()?;
2527 }
2528 PatKind::Path(None, ref path) => {
2529 self.print_path(path, true, 0, false)?;
2530 }
2531 PatKind::Path(Some(ref qself), ref path) => {
2532 self.print_qpath(path, qself, false)?;
2533 }
2534 PatKind::Struct(ref path, ref fields, etc) => {
2535 self.print_path(path, true, 0, false)?;
2536 self.nbsp()?;
2537 self.word_space("{")?;
2538 self.commasep_cmnt(
2539 Consistent, &fields[..],
2540 |s, f| {
2541 s.cbox(INDENT_UNIT)?;
2542 if !f.node.is_shorthand {
2543 s.print_ident(f.node.ident)?;
2544 s.word_nbsp(":")?;
2545 }
2546 s.print_pat(&f.node.pat)?;
2547 s.end()
2548 },
2549 |f| f.node.pat.span)?;
2550 if etc {
2551 if !fields.is_empty() { self.word_space(",")?; }
2552 self.s.word("..")?;
2553 }
2554 self.s.space()?;
2555 self.s.word("}")?;
2556 }
2557 PatKind::Tuple(ref elts, ddpos) => {
2558 self.popen()?;
2559 if let Some(ddpos) = ddpos {
2560 self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?;
2561 if ddpos != 0 {
2562 self.word_space(",")?;
2563 }
2564 self.s.word("..")?;
2565 if ddpos != elts.len() {
2566 self.s.word(",")?;
2567 self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?;
2568 }
2569 } else {
2570 self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?;
2571 if elts.len() == 1 {
2572 self.s.word(",")?;
2573 }
2574 }
2575 self.pclose()?;
2576 }
2577 PatKind::Box(ref inner) => {
2578 self.s.word("box ")?;
2579 self.print_pat(inner)?;
2580 }
2581 PatKind::Ref(ref inner, mutbl) => {
2582 self.s.word("&")?;
2583 if mutbl == ast::Mutability::Mutable {
2584 self.s.word("mut ")?;
2585 }
2586 self.print_pat(inner)?;
2587 }
2588 PatKind::Lit(ref e) => self.print_expr(&**e)?,
2589 PatKind::Range(ref begin, ref end, ref end_kind) => {
2590 self.print_expr(begin)?;
2591 self.s.space()?;
2592 match *end_kind {
2593 RangeEnd::Included(RangeSyntax::DotDotDot) => self.s.word("...")?,
2594 RangeEnd::Included(RangeSyntax::DotDotEq) => self.s.word("..=")?,
2595 RangeEnd::Excluded => self.s.word("..")?,
2596 }
2597 self.print_expr(end)?;
2598 }
2599 PatKind::Slice(ref before, ref slice, ref after) => {
2600 self.s.word("[")?;
2601 self.commasep(Inconsistent,
2602 &before[..],
2603 |s, p| s.print_pat(p))?;
2604 if let Some(ref p) = *slice {
2605 if !before.is_empty() { self.word_space(",")?; }
2606 if p.node != PatKind::Wild {
2607 self.print_pat(p)?;
2608 }
2609 self.s.word("..")?;
2610 if !after.is_empty() { self.word_space(",")?; }
2611 }
2612 self.commasep(Inconsistent,
2613 &after[..],
2614 |s, p| s.print_pat(p))?;
2615 self.s.word("]")?;
2616 }
2617 PatKind::Mac(ref m) => self.print_mac(m, token::Paren)?,
2618 }
2619 self.ann.post(self, NodePat(pat))
2620 }
2621
2622 fn print_arm(&mut self, arm: &ast::Arm) -> io::Result<()> {
2623 // I have no idea why this check is necessary, but here it
2624 // is :(
2625 if arm.attrs.is_empty() {
2626 self.s.space()?;
2627 }
2628 self.cbox(INDENT_UNIT)?;
2629 self.ibox(0)?;
2630 self.maybe_print_comment(arm.pats[0].span.lo())?;
2631 self.print_outer_attributes(&arm.attrs)?;
2632 let mut first = true;
2633 for p in &arm.pats {
2634 if first {
2635 first = false;
2636 } else {
2637 self.s.space()?;
2638 self.word_space("|")?;
2639 }
2640 self.print_pat(p)?;
2641 }
2642 self.s.space()?;
2643 if let Some(ref e) = arm.guard {
2644 self.word_space("if")?;
2645 self.print_expr(e)?;
2646 self.s.space()?;
2647 }
2648 self.word_space("=>")?;
2649
2650 match arm.body.node {
2651 ast::ExprKind::Block(ref blk) => {
2652 // the block will close the pattern's ibox
2653 self.print_block_unclosed_indent(blk, INDENT_UNIT)?;
2654
2655 // If it is a user-provided unsafe block, print a comma after it
2656 if let BlockCheckMode::Unsafe(ast::UserProvided) = blk.rules {
2657 self.s.word(",")?;
2658 }
2659 }
2660 _ => {
2661 self.end()?; // close the ibox for the pattern
2662 self.print_expr(&arm.body)?;
2663 self.s.word(",")?;
2664 }
2665 }
2666 self.end() // close enclosing cbox
2667 }
2668
2669 fn print_explicit_self(&mut self, explicit_self: &ast::ExplicitSelf) -> io::Result<()> {
2670 match explicit_self.node {
2671 SelfKind::Value(m) => {
2672 self.print_mutability(m)?;
2673 self.s.word("self")
2674 }
2675 SelfKind::Region(ref lt, m) => {
2676 self.s.word("&")?;
2677 self.print_opt_lifetime(lt)?;
2678 self.print_mutability(m)?;
2679 self.s.word("self")
2680 }
2681 SelfKind::Explicit(ref typ, m) => {
2682 self.print_mutability(m)?;
2683 self.s.word("self")?;
2684 self.word_space(":")?;
2685 self.print_type(typ)
2686 }
2687 }
2688 }
2689
2690 pub fn print_fn(&mut self,
2691 decl: &ast::FnDecl,
2692 unsafety: ast::Unsafety,
2693 constness: ast::Constness,
2694 abi: abi::Abi,
2695 name: Option<ast::Ident>,
2696 generics: &ast::Generics,
2697 vis: &ast::Visibility) -> io::Result<()> {
2698 self.print_fn_header_info(unsafety, constness, abi, vis)?;
2699
2700 if let Some(name) = name {
2701 self.nbsp()?;
2702 self.print_ident(name)?;
2703 }
2704 self.print_generics(generics)?;
2705 self.print_fn_args_and_ret(decl)?;
2706 self.print_where_clause(&generics.where_clause)
2707 }
2708
2709 pub fn print_fn_args_and_ret(&mut self, decl: &ast::FnDecl)
2710 -> io::Result<()> {
2711 self.popen()?;
2712 self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, false))?;
2713 if decl.variadic {
2714 self.s.word(", ...")?;
2715 }
2716 self.pclose()?;
2717
2718 self.print_fn_output(decl)
2719 }
2720
2721 pub fn print_fn_block_args(
2722 &mut self,
2723 decl: &ast::FnDecl)
2724 -> io::Result<()> {
2725 self.s.word("|")?;
2726 self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, true))?;
2727 self.s.word("|")?;
2728
2729 if let ast::FunctionRetTy::Default(..) = decl.output {
2730 return Ok(());
2731 }
2732
2733 self.space_if_not_bol()?;
2734 self.word_space("->")?;
2735 match decl.output {
2736 ast::FunctionRetTy::Ty(ref ty) => {
2737 self.print_type(ty)?;
2738 self.maybe_print_comment(ty.span.lo())
2739 }
2740 ast::FunctionRetTy::Default(..) => unreachable!(),
2741 }
2742 }
2743
2744 pub fn print_capture_clause(&mut self, capture_clause: ast::CaptureBy)
2745 -> io::Result<()> {
2746 match capture_clause {
2747 ast::CaptureBy::Value => self.word_space("move"),
2748 ast::CaptureBy::Ref => Ok(()),
2749 }
2750 }
2751
2752 pub fn print_bounds(&mut self,
2753 prefix: &str,
2754 bounds: &[ast::TyParamBound])
2755 -> io::Result<()> {
2756 if !bounds.is_empty() {
2757 self.s.word(prefix)?;
2758 let mut first = true;
2759 for bound in bounds {
2760 self.nbsp()?;
2761 if first {
2762 first = false;
2763 } else {
2764 self.word_space("+")?;
2765 }
2766
2767 (match *bound {
2768 TraitTyParamBound(ref tref, TraitBoundModifier::None) => {
2769 self.print_poly_trait_ref(tref)
2770 }
2771 TraitTyParamBound(ref tref, TraitBoundModifier::Maybe) => {
2772 self.s.word("?")?;
2773 self.print_poly_trait_ref(tref)
2774 }
2775 RegionTyParamBound(ref lt) => {
2776 self.print_lifetime(lt)
2777 }
2778 })?
2779 }
2780 Ok(())
2781 } else {
2782 Ok(())
2783 }
2784 }
2785
2786 pub fn print_lifetime(&mut self,
2787 lifetime: &ast::Lifetime)
2788 -> io::Result<()>
2789 {
2790 self.print_name(lifetime.ident.name)
2791 }
2792
2793 pub fn print_lifetime_bounds(&mut self,
2794 lifetime: &ast::Lifetime,
2795 bounds: &[ast::Lifetime])
2796 -> io::Result<()>
2797 {
2798 self.print_lifetime(lifetime)?;
2799 if !bounds.is_empty() {
2800 self.s.word(": ")?;
2801 for (i, bound) in bounds.iter().enumerate() {
2802 if i != 0 {
2803 self.s.word(" + ")?;
2804 }
2805 self.print_lifetime(bound)?;
2806 }
2807 }
2808 Ok(())
2809 }
2810
2811 pub fn print_generics(&mut self,
2812 generics: &ast::Generics)
2813 -> io::Result<()>
2814 {
2815 let total = generics.lifetimes.len() + generics.ty_params.len();
2816 if total == 0 {
2817 return Ok(());
2818 }
2819
2820 self.s.word("<")?;
2821
2822 let mut ints = Vec::new();
2823 for i in 0..total {
2824 ints.push(i);
2825 }
2826
2827 self.commasep(Inconsistent, &ints[..], |s, &idx| {
2828 if idx < generics.lifetimes.len() {
2829 let lifetime_def = &generics.lifetimes[idx];
2830 s.print_outer_attributes_inline(&lifetime_def.attrs)?;
2831 s.print_lifetime_bounds(&lifetime_def.lifetime, &lifetime_def.bounds)
2832 } else {
2833 let idx = idx - generics.lifetimes.len();
2834 let param = &generics.ty_params[idx];
2835 s.print_ty_param(param)
2836 }
2837 })?;
2838
2839 self.s.word(">")?;
2840 Ok(())
2841 }
2842
2843 pub fn print_ty_param(&mut self, param: &ast::TyParam) -> io::Result<()> {
2844 self.print_outer_attributes_inline(&param.attrs)?;
2845 self.print_ident(param.ident)?;
2846 self.print_bounds(":", &param.bounds)?;
2847 match param.default {
2848 Some(ref default) => {
2849 self.s.space()?;
2850 self.word_space("=")?;
2851 self.print_type(default)
2852 }
2853 _ => Ok(())
2854 }
2855 }
2856
2857 pub fn print_where_clause(&mut self, where_clause: &ast::WhereClause)
2858 -> io::Result<()> {
2859 if where_clause.predicates.is_empty() {
2860 return Ok(())
2861 }
2862
2863 self.s.space()?;
2864 self.word_space("where")?;
2865
2866 for (i, predicate) in where_clause.predicates.iter().enumerate() {
2867 if i != 0 {
2868 self.word_space(",")?;
2869 }
2870
2871 match *predicate {
2872 ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate{ref bound_lifetimes,
2873 ref bounded_ty,
2874 ref bounds,
2875 ..}) => {
2876 self.print_formal_lifetime_list(bound_lifetimes)?;
2877 self.print_type(bounded_ty)?;
2878 self.print_bounds(":", bounds)?;
2879 }
2880 ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate{ref lifetime,
2881 ref bounds,
2882 ..}) => {
2883 self.print_lifetime_bounds(lifetime, bounds)?;
2884 }
2885 ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{ref lhs_ty,
2886 ref rhs_ty,
2887 ..}) => {
2888 self.print_type(lhs_ty)?;
2889 self.s.space()?;
2890 self.word_space("=")?;
2891 self.print_type(rhs_ty)?;
2892 }
2893 }
2894 }
2895
2896 Ok(())
2897 }
2898
2899 pub fn print_view_path(&mut self, vp: &ast::ViewPath) -> io::Result<()> {
2900 match vp.node {
2901 ast::ViewPathSimple(ident, ref path) => {
2902 self.print_path(path, false, 0, true)?;
2903
2904 if path.segments.last().unwrap().identifier.name !=
2905 ident.name {
2906 self.s.space()?;
2907 self.word_space("as")?;
2908 self.print_ident(ident)?;
2909 }
2910
2911 Ok(())
2912 }
2913
2914 ast::ViewPathGlob(ref path) => {
2915 self.print_path(path, false, 0, true)?;
2916 self.s.word("::*")
2917 }
2918
2919 ast::ViewPathList(ref path, ref idents) => {
2920 if path.segments.is_empty() {
2921 self.s.word("{")?;
2922 } else {
2923 self.print_path(path, false, 0, true)?;
2924 self.s.word("::{")?;
2925 }
2926 self.commasep(Inconsistent, &idents[..], |s, w| {
2927 s.print_ident(w.node.name)?;
2928 if let Some(ident) = w.node.rename {
2929 s.s.space()?;
2930 s.word_space("as")?;
2931 s.print_ident(ident)?;
2932 }
2933 Ok(())
2934 })?;
2935 self.s.word("}")
2936 }
2937 }
2938 }
2939
2940 pub fn print_mutability(&mut self,
2941 mutbl: ast::Mutability) -> io::Result<()> {
2942 match mutbl {
2943 ast::Mutability::Mutable => self.word_nbsp("mut"),
2944 ast::Mutability::Immutable => Ok(()),
2945 }
2946 }
2947
2948 pub fn print_mt(&mut self, mt: &ast::MutTy) -> io::Result<()> {
2949 self.print_mutability(mt.mutbl)?;
2950 self.print_type(&mt.ty)
2951 }
2952
2953 pub fn print_arg(&mut self, input: &ast::Arg, is_closure: bool) -> io::Result<()> {
2954 self.ibox(INDENT_UNIT)?;
2955 match input.ty.node {
2956 ast::TyKind::Infer if is_closure => self.print_pat(&input.pat)?,
2957 _ => {
2958 if let Some(eself) = input.to_self() {
2959 self.print_explicit_self(&eself)?;
2960 } else {
2961 let invalid = if let PatKind::Ident(_, ident, _) = input.pat.node {
2962 ident.node.name == keywords::Invalid.name()
2963 } else {
2964 false
2965 };
2966 if !invalid {
2967 self.print_pat(&input.pat)?;
2968 self.s.word(":")?;
2969 self.s.space()?;
2970 }
2971 self.print_type(&input.ty)?;
2972 }
2973 }
2974 }
2975 self.end()
2976 }
2977
2978 pub fn print_fn_output(&mut self, decl: &ast::FnDecl) -> io::Result<()> {
2979 if let ast::FunctionRetTy::Default(..) = decl.output {
2980 return Ok(());
2981 }
2982
2983 self.space_if_not_bol()?;
2984 self.ibox(INDENT_UNIT)?;
2985 self.word_space("->")?;
2986 match decl.output {
2987 ast::FunctionRetTy::Default(..) => unreachable!(),
2988 ast::FunctionRetTy::Ty(ref ty) =>
2989 self.print_type(ty)?
2990 }
2991 self.end()?;
2992
2993 match decl.output {
2994 ast::FunctionRetTy::Ty(ref output) => self.maybe_print_comment(output.span.lo()),
2995 _ => Ok(())
2996 }
2997 }
2998
2999 pub fn print_ty_fn(&mut self,
3000 abi: abi::Abi,
3001 unsafety: ast::Unsafety,
3002 decl: &ast::FnDecl,
3003 name: Option<ast::Ident>,
3004 generics: &ast::Generics)
3005 -> io::Result<()> {
3006 self.ibox(INDENT_UNIT)?;
3007 if !generics.lifetimes.is_empty() || !generics.ty_params.is_empty() {
3008 self.s.word("for")?;
3009 self.print_generics(generics)?;
3010 }
3011 let generics = ast::Generics {
3012 lifetimes: Vec::new(),
3013 ty_params: Vec::new(),
3014 where_clause: ast::WhereClause {
3015 id: ast::DUMMY_NODE_ID,
3016 predicates: Vec::new(),
3017 span: syntax_pos::DUMMY_SP,
3018 },
3019 span: syntax_pos::DUMMY_SP,
3020 };
3021 self.print_fn(decl,
3022 unsafety,
3023 ast::Constness::NotConst,
3024 abi,
3025 name,
3026 &generics,
3027 &ast::Visibility::Inherited)?;
3028 self.end()
3029 }
3030
3031 pub fn maybe_print_trailing_comment(&mut self, span: syntax_pos::Span,
3032 next_pos: Option<BytePos>)
3033 -> io::Result<()> {
3034 let cm = match self.cm {
3035 Some(cm) => cm,
3036 _ => return Ok(())
3037 };
3038 if let Some(ref cmnt) = self.next_comment() {
3039 if cmnt.style != comments::Trailing { return Ok(()) }
3040 let span_line = cm.lookup_char_pos(span.hi());
3041 let comment_line = cm.lookup_char_pos(cmnt.pos);
3042 let next = next_pos.unwrap_or(cmnt.pos + BytePos(1));
3043 if span.hi() < cmnt.pos && cmnt.pos < next && span_line.line == comment_line.line {
3044 self.print_comment(cmnt)?;
3045 }
3046 }
3047 Ok(())
3048 }
3049
3050 pub fn print_remaining_comments(&mut self) -> io::Result<()> {
3051 // If there aren't any remaining comments, then we need to manually
3052 // make sure there is a line break at the end.
3053 if self.next_comment().is_none() {
3054 self.s.hardbreak()?;
3055 }
3056 while let Some(ref cmnt) = self.next_comment() {
3057 self.print_comment(cmnt)?;
3058 }
3059 Ok(())
3060 }
3061
3062 pub fn print_opt_abi_and_extern_if_nondefault(&mut self,
3063 opt_abi: Option<Abi>)
3064 -> io::Result<()> {
3065 match opt_abi {
3066 Some(Abi::Rust) => Ok(()),
3067 Some(abi) => {
3068 self.word_nbsp("extern")?;
3069 self.word_nbsp(&abi.to_string())
3070 }
3071 None => Ok(())
3072 }
3073 }
3074
3075 pub fn print_extern_opt_abi(&mut self,
3076 opt_abi: Option<Abi>) -> io::Result<()> {
3077 match opt_abi {
3078 Some(abi) => {
3079 self.word_nbsp("extern")?;
3080 self.word_nbsp(&abi.to_string())
3081 }
3082 None => Ok(())
3083 }
3084 }
3085
3086 pub fn print_fn_header_info(&mut self,
3087 unsafety: ast::Unsafety,
3088 constness: ast::Constness,
3089 abi: Abi,
3090 vis: &ast::Visibility) -> io::Result<()> {
3091 self.s.word(&visibility_qualified(vis, ""))?;
3092
3093 match constness {
3094 ast::Constness::NotConst => {}
3095 ast::Constness::Const => self.word_nbsp("const")?
3096 }
3097
3098 self.print_unsafety(unsafety)?;
3099
3100 if abi != Abi::Rust {
3101 self.word_nbsp("extern")?;
3102 self.word_nbsp(&abi.to_string())?;
3103 }
3104
3105 self.s.word("fn")
3106 }
3107
3108 pub fn print_unsafety(&mut self, s: ast::Unsafety) -> io::Result<()> {
3109 match s {
3110 ast::Unsafety::Normal => Ok(()),
3111 ast::Unsafety::Unsafe => self.word_nbsp("unsafe"),
3112 }
3113 }
3114 }
3115
3116 fn repeat(s: &str, n: usize) -> String { iter::repeat(s).take(n).collect() }
3117
3118 #[cfg(test)]
3119 mod tests {
3120 use super::*;
3121
3122 use ast;
3123 use codemap;
3124 use syntax_pos;
3125
3126 #[test]
3127 fn test_fun_to_string() {
3128 let abba_ident = ast::Ident::from_str("abba");
3129
3130 let decl = ast::FnDecl {
3131 inputs: Vec::new(),
3132 output: ast::FunctionRetTy::Default(syntax_pos::DUMMY_SP),
3133 variadic: false
3134 };
3135 let generics = ast::Generics::default();
3136 assert_eq!(fun_to_string(&decl, ast::Unsafety::Normal,
3137 ast::Constness::NotConst,
3138 abba_ident, &generics),
3139 "fn abba()");
3140 }
3141
3142 #[test]
3143 fn test_variant_to_string() {
3144 let ident = ast::Ident::from_str("principal_skinner");
3145
3146 let var = codemap::respan(syntax_pos::DUMMY_SP, ast::Variant_ {
3147 name: ident,
3148 attrs: Vec::new(),
3149 // making this up as I go.... ?
3150 data: ast::VariantData::Unit(ast::DUMMY_NODE_ID),
3151 disr_expr: None,
3152 });
3153
3154 let varstr = variant_to_string(&var);
3155 assert_eq!(varstr, "principal_skinner");
3156 }
3157 }
backport for Debian buster