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1 // Copyright 2015 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 syntax::abi::Abi;
14 use syntax::ast;
15 use syntax::codemap::{self, CodeMap, BytePos, Spanned};
16 use syntax::errors;
17 use syntax::parse::token::{self, BinOpToken};
18 use syntax::parse::lexer::comments;
19 use syntax::parse;
20 use syntax::print::pp::{self, break_offset, word, space, hardbreak};
21 use syntax::print::pp::{Breaks, eof};
22 use syntax::print::pp::Breaks::{Consistent, Inconsistent};
23 use syntax::print::pprust::{self as ast_pp, PrintState};
24 use syntax::ptr::P;
25
26 use hir;
27 use hir::{Crate, PatKind, RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
28
29 use std::io::{self, Write, Read};
30
31 pub enum AnnNode<'a> {
32 NodeName(&'a ast::Name),
33 NodeBlock(&'a hir::Block),
34 NodeItem(&'a hir::Item),
35 NodeSubItem(ast::NodeId),
36 NodeExpr(&'a hir::Expr),
37 NodePat(&'a hir::Pat),
38 }
39
40 pub trait PpAnn {
41 fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> {
42 Ok(())
43 }
44 fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> {
45 Ok(())
46 }
47 }
48
49 #[derive(Copy, Clone)]
50 pub struct NoAnn;
51
52 impl PpAnn for NoAnn {}
53
54
55 pub struct State<'a> {
56 krate: Option<&'a Crate>,
57 pub s: pp::Printer<'a>,
58 cm: Option<&'a CodeMap>,
59 comments: Option<Vec<comments::Comment>>,
60 literals: Option<Vec<comments::Literal>>,
61 cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral,
62 boxes: Vec<pp::Breaks>,
63 ann: &'a (PpAnn + 'a),
64 }
65
66 impl<'a> PrintState<'a> for State<'a> {
67 fn writer(&mut self) -> &mut pp::Printer<'a> {
68 &mut self.s
69 }
70
71 fn boxes(&mut self) -> &mut Vec<pp::Breaks> {
72 &mut self.boxes
73 }
74
75 fn comments(&mut self) -> &mut Option<Vec<comments::Comment>> {
76 &mut self.comments
77 }
78
79 fn cur_cmnt_and_lit(&mut self) -> &mut ast_pp::CurrentCommentAndLiteral {
80 &mut self.cur_cmnt_and_lit
81 }
82
83 fn literals(&self) -> &Option<Vec<comments::Literal>> {
84 &self.literals
85 }
86 }
87
88 pub fn rust_printer<'a>(writer: Box<Write + 'a>, krate: Option<&'a Crate>) -> State<'a> {
89 static NO_ANN: NoAnn = NoAnn;
90 rust_printer_annotated(writer, &NO_ANN, krate)
91 }
92
93 pub fn rust_printer_annotated<'a>(writer: Box<Write + 'a>,
94 ann: &'a PpAnn,
95 krate: Option<&'a Crate>)
96 -> State<'a> {
97 State {
98 krate: krate,
99 s: pp::mk_printer(writer, default_columns),
100 cm: None,
101 comments: None,
102 literals: None,
103 cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral {
104 cur_cmnt: 0,
105 cur_lit: 0,
106 },
107 boxes: Vec::new(),
108 ann: ann,
109 }
110 }
111
112 #[allow(non_upper_case_globals)]
113 pub const indent_unit: usize = 4;
114
115 #[allow(non_upper_case_globals)]
116 pub const default_columns: usize = 78;
117
118
119 /// Requires you to pass an input filename and reader so that
120 /// it can scan the input text for comments and literals to
121 /// copy forward.
122 pub fn print_crate<'a>(cm: &'a CodeMap,
123 span_diagnostic: &errors::Handler,
124 krate: &hir::Crate,
125 filename: String,
126 input: &mut Read,
127 out: Box<Write + 'a>,
128 ann: &'a PpAnn,
129 is_expanded: bool)
130 -> io::Result<()> {
131 let mut s = State::new_from_input(cm, span_diagnostic, filename, input,
132 out, ann, is_expanded, Some(krate));
133
134 // When printing the AST, we sometimes need to inject `#[no_std]` here.
135 // Since you can't compile the HIR, it's not necessary.
136
137 s.print_mod(&krate.module, &krate.attrs)?;
138 s.print_remaining_comments()?;
139 eof(&mut s.s)
140 }
141
142 impl<'a> State<'a> {
143 pub fn new_from_input(cm: &'a CodeMap,
144 span_diagnostic: &errors::Handler,
145 filename: String,
146 input: &mut Read,
147 out: Box<Write + 'a>,
148 ann: &'a PpAnn,
149 is_expanded: bool,
150 krate: Option<&'a Crate>)
151 -> State<'a> {
152 let (cmnts, lits) = comments::gather_comments_and_literals(span_diagnostic,
153 filename,
154 input);
155
156 State::new(cm,
157 out,
158 ann,
159 Some(cmnts),
160 // If the code is post expansion, don't use the table of
161 // literals, since it doesn't correspond with the literals
162 // in the AST anymore.
163 if is_expanded {
164 None
165 } else {
166 Some(lits)
167 },
168 krate)
169 }
170
171 pub fn new(cm: &'a CodeMap,
172 out: Box<Write + 'a>,
173 ann: &'a PpAnn,
174 comments: Option<Vec<comments::Comment>>,
175 literals: Option<Vec<comments::Literal>>,
176 krate: Option<&'a Crate>)
177 -> State<'a> {
178 State {
179 krate: krate,
180 s: pp::mk_printer(out, default_columns),
181 cm: Some(cm),
182 comments: comments.clone(),
183 literals: literals.clone(),
184 cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral {
185 cur_cmnt: 0,
186 cur_lit: 0,
187 },
188 boxes: Vec::new(),
189 ann: ann,
190 }
191 }
192 }
193
194 pub fn to_string<F>(f: F) -> String
195 where F: FnOnce(&mut State) -> io::Result<()>
196 {
197 let mut wr = Vec::new();
198 {
199 let mut printer = rust_printer(Box::new(&mut wr), None);
200 f(&mut printer).unwrap();
201 eof(&mut printer.s).unwrap();
202 }
203 String::from_utf8(wr).unwrap()
204 }
205
206 pub fn binop_to_string(op: BinOpToken) -> &'static str {
207 match op {
208 token::Plus => "+",
209 token::Minus => "-",
210 token::Star => "*",
211 token::Slash => "/",
212 token::Percent => "%",
213 token::Caret => "^",
214 token::And => "&",
215 token::Or => "|",
216 token::Shl => "<<",
217 token::Shr => ">>",
218 }
219 }
220
221 pub fn ty_to_string(ty: &hir::Ty) -> String {
222 to_string(|s| s.print_type(ty))
223 }
224
225 pub fn bounds_to_string(bounds: &[hir::TyParamBound]) -> String {
226 to_string(|s| s.print_bounds("", bounds))
227 }
228
229 pub fn pat_to_string(pat: &hir::Pat) -> String {
230 to_string(|s| s.print_pat(pat))
231 }
232
233 pub fn arm_to_string(arm: &hir::Arm) -> String {
234 to_string(|s| s.print_arm(arm))
235 }
236
237 pub fn expr_to_string(e: &hir::Expr) -> String {
238 to_string(|s| s.print_expr(e))
239 }
240
241 pub fn lifetime_to_string(e: &hir::Lifetime) -> String {
242 to_string(|s| s.print_lifetime(e))
243 }
244
245 pub fn stmt_to_string(stmt: &hir::Stmt) -> String {
246 to_string(|s| s.print_stmt(stmt))
247 }
248
249 pub fn item_to_string(i: &hir::Item) -> String {
250 to_string(|s| s.print_item(i))
251 }
252
253 pub fn impl_item_to_string(i: &hir::ImplItem) -> String {
254 to_string(|s| s.print_impl_item(i))
255 }
256
257 pub fn trait_item_to_string(i: &hir::TraitItem) -> String {
258 to_string(|s| s.print_trait_item(i))
259 }
260
261 pub fn generics_to_string(generics: &hir::Generics) -> String {
262 to_string(|s| s.print_generics(generics))
263 }
264
265 pub fn where_clause_to_string(i: &hir::WhereClause) -> String {
266 to_string(|s| s.print_where_clause(i))
267 }
268
269 pub fn fn_block_to_string(p: &hir::FnDecl) -> String {
270 to_string(|s| s.print_fn_block_args(p))
271 }
272
273 pub fn path_to_string(p: &hir::Path) -> String {
274 to_string(|s| s.print_path(p, false, 0))
275 }
276
277 pub fn name_to_string(name: ast::Name) -> String {
278 to_string(|s| s.print_name(name))
279 }
280
281 pub fn fun_to_string(decl: &hir::FnDecl,
282 unsafety: hir::Unsafety,
283 constness: hir::Constness,
284 name: ast::Name,
285 opt_explicit_self: Option<&hir::ExplicitSelf_>,
286 generics: &hir::Generics)
287 -> String {
288 to_string(|s| {
289 s.head("")?;
290 s.print_fn(decl,
291 unsafety,
292 constness,
293 Abi::Rust,
294 Some(name),
295 generics,
296 opt_explicit_self,
297 &hir::Inherited)?;
298 s.end()?; // Close the head box
299 s.end() // Close the outer box
300 })
301 }
302
303 pub fn block_to_string(blk: &hir::Block) -> String {
304 to_string(|s| {
305 // containing cbox, will be closed by print-block at }
306 s.cbox(indent_unit)?;
307 // head-ibox, will be closed by print-block after {
308 s.ibox(0)?;
309 s.print_block(blk)
310 })
311 }
312
313 pub fn explicit_self_to_string(explicit_self: &hir::ExplicitSelf_) -> String {
314 to_string(|s| s.print_explicit_self(explicit_self, hir::MutImmutable).map(|_| {}))
315 }
316
317 pub fn variant_to_string(var: &hir::Variant) -> String {
318 to_string(|s| s.print_variant(var))
319 }
320
321 pub fn arg_to_string(arg: &hir::Arg) -> String {
322 to_string(|s| s.print_arg(arg, false))
323 }
324
325 pub fn visibility_qualified(vis: &hir::Visibility, s: &str) -> String {
326 match *vis {
327 hir::Public => format!("pub {}", s),
328 hir::Inherited => s.to_string(),
329 }
330 }
331
332 fn needs_parentheses(expr: &hir::Expr) -> bool {
333 match expr.node {
334 hir::ExprAssign(..) |
335 hir::ExprBinary(..) |
336 hir::ExprClosure(..) |
337 hir::ExprAssignOp(..) |
338 hir::ExprCast(..) |
339 hir::ExprType(..) => true,
340 _ => false,
341 }
342 }
343
344 impl<'a> State<'a> {
345 pub fn cbox(&mut self, u: usize) -> io::Result<()> {
346 self.boxes.push(pp::Breaks::Consistent);
347 pp::cbox(&mut self.s, u)
348 }
349
350 pub fn nbsp(&mut self) -> io::Result<()> {
351 word(&mut self.s, " ")
352 }
353
354 pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> {
355 word(&mut self.s, w)?;
356 self.nbsp()
357 }
358
359 pub fn head(&mut self, w: &str) -> io::Result<()> {
360 // outer-box is consistent
361 self.cbox(indent_unit)?;
362 // head-box is inconsistent
363 self.ibox(w.len() + 1)?;
364 // keyword that starts the head
365 if !w.is_empty() {
366 self.word_nbsp(w)?;
367 }
368 Ok(())
369 }
370
371 pub fn bopen(&mut self) -> io::Result<()> {
372 word(&mut self.s, "{")?;
373 self.end() // close the head-box
374 }
375
376 pub fn bclose_(&mut self, span: codemap::Span, indented: usize) -> io::Result<()> {
377 self.bclose_maybe_open(span, indented, true)
378 }
379 pub fn bclose_maybe_open(&mut self,
380 span: codemap::Span,
381 indented: usize,
382 close_box: bool)
383 -> io::Result<()> {
384 self.maybe_print_comment(span.hi)?;
385 self.break_offset_if_not_bol(1, -(indented as isize))?;
386 word(&mut self.s, "}")?;
387 if close_box {
388 self.end()?; // close the outer-box
389 }
390 Ok(())
391 }
392 pub fn bclose(&mut self, span: codemap::Span) -> io::Result<()> {
393 self.bclose_(span, indent_unit)
394 }
395
396 pub fn in_cbox(&self) -> bool {
397 match self.boxes.last() {
398 Some(&last_box) => last_box == pp::Breaks::Consistent,
399 None => false,
400 }
401 }
402 pub fn space_if_not_bol(&mut self) -> io::Result<()> {
403 if !self.is_bol() {
404 space(&mut self.s)?;
405 }
406 Ok(())
407 }
408 pub fn break_offset_if_not_bol(&mut self, n: usize, off: isize) -> io::Result<()> {
409 if !self.is_bol() {
410 break_offset(&mut self.s, n, off)
411 } else {
412 if off != 0 && self.s.last_token().is_hardbreak_tok() {
413 // We do something pretty sketchy here: tuck the nonzero
414 // offset-adjustment we were going to deposit along with the
415 // break into the previous hardbreak.
416 self.s.replace_last_token(pp::hardbreak_tok_offset(off));
417 }
418 Ok(())
419 }
420 }
421
422 // Synthesizes a comment that was not textually present in the original source
423 // file.
424 pub fn synth_comment(&mut self, text: String) -> io::Result<()> {
425 word(&mut self.s, "/*")?;
426 space(&mut self.s)?;
427 word(&mut self.s, &text[..])?;
428 space(&mut self.s)?;
429 word(&mut self.s, "*/")
430 }
431
432
433 pub fn commasep_cmnt<T, F, G>(&mut self,
434 b: Breaks,
435 elts: &[T],
436 mut op: F,
437 mut get_span: G)
438 -> io::Result<()>
439 where F: FnMut(&mut State, &T) -> io::Result<()>,
440 G: FnMut(&T) -> codemap::Span
441 {
442 self.rbox(0, b)?;
443 let len = elts.len();
444 let mut i = 0;
445 for elt in elts {
446 self.maybe_print_comment(get_span(elt).hi)?;
447 op(self, elt)?;
448 i += 1;
449 if i < len {
450 word(&mut self.s, ",")?;
451 self.maybe_print_trailing_comment(get_span(elt), Some(get_span(&elts[i]).hi))?;
452 self.space_if_not_bol()?;
453 }
454 }
455 self.end()
456 }
457
458 pub fn commasep_exprs(&mut self, b: Breaks, exprs: &[P<hir::Expr>]) -> io::Result<()> {
459 self.commasep_cmnt(b, exprs, |s, e| s.print_expr(&e), |e| e.span)
460 }
461
462 pub fn print_mod(&mut self, _mod: &hir::Mod, attrs: &[ast::Attribute]) -> io::Result<()> {
463 self.print_inner_attributes(attrs)?;
464 for item_id in &_mod.item_ids {
465 self.print_item_id(item_id)?;
466 }
467 Ok(())
468 }
469
470 pub fn print_foreign_mod(&mut self,
471 nmod: &hir::ForeignMod,
472 attrs: &[ast::Attribute])
473 -> io::Result<()> {
474 self.print_inner_attributes(attrs)?;
475 for item in &nmod.items {
476 self.print_foreign_item(item)?;
477 }
478 Ok(())
479 }
480
481 pub fn print_opt_lifetime(&mut self, lifetime: &Option<hir::Lifetime>) -> io::Result<()> {
482 if let Some(l) = *lifetime {
483 self.print_lifetime(&l)?;
484 self.nbsp()?;
485 }
486 Ok(())
487 }
488
489 pub fn print_type(&mut self, ty: &hir::Ty) -> io::Result<()> {
490 self.maybe_print_comment(ty.span.lo)?;
491 self.ibox(0)?;
492 match ty.node {
493 hir::TyVec(ref ty) => {
494 word(&mut self.s, "[")?;
495 self.print_type(&ty)?;
496 word(&mut self.s, "]")?;
497 }
498 hir::TyPtr(ref mt) => {
499 word(&mut self.s, "*")?;
500 match mt.mutbl {
501 hir::MutMutable => self.word_nbsp("mut")?,
502 hir::MutImmutable => self.word_nbsp("const")?,
503 }
504 self.print_type(&mt.ty)?;
505 }
506 hir::TyRptr(ref lifetime, ref mt) => {
507 word(&mut self.s, "&")?;
508 self.print_opt_lifetime(lifetime)?;
509 self.print_mt(mt)?;
510 }
511 hir::TyTup(ref elts) => {
512 self.popen()?;
513 self.commasep(Inconsistent, &elts[..], |s, ty| s.print_type(&ty))?;
514 if elts.len() == 1 {
515 word(&mut self.s, ",")?;
516 }
517 self.pclose()?;
518 }
519 hir::TyBareFn(ref f) => {
520 let generics = hir::Generics {
521 lifetimes: f.lifetimes.clone(),
522 ty_params: hir::HirVec::new(),
523 where_clause: hir::WhereClause {
524 id: ast::DUMMY_NODE_ID,
525 predicates: hir::HirVec::new(),
526 },
527 };
528 self.print_ty_fn(f.abi, f.unsafety, &f.decl, None, &generics, None)?;
529 }
530 hir::TyPath(None, ref path) => {
531 self.print_path(path, false, 0)?;
532 }
533 hir::TyPath(Some(ref qself), ref path) => {
534 self.print_qpath(path, qself, false)?
535 }
536 hir::TyObjectSum(ref ty, ref bounds) => {
537 self.print_type(&ty)?;
538 self.print_bounds("+", &bounds[..])?;
539 }
540 hir::TyPolyTraitRef(ref bounds) => {
541 self.print_bounds("", &bounds[..])?;
542 }
543 hir::TyFixedLengthVec(ref ty, ref v) => {
544 word(&mut self.s, "[")?;
545 self.print_type(&ty)?;
546 word(&mut self.s, "; ")?;
547 self.print_expr(&v)?;
548 word(&mut self.s, "]")?;
549 }
550 hir::TyTypeof(ref e) => {
551 word(&mut self.s, "typeof(")?;
552 self.print_expr(&e)?;
553 word(&mut self.s, ")")?;
554 }
555 hir::TyInfer => {
556 word(&mut self.s, "_")?;
557 }
558 }
559 self.end()
560 }
561
562 pub fn print_foreign_item(&mut self, item: &hir::ForeignItem) -> io::Result<()> {
563 self.hardbreak_if_not_bol()?;
564 self.maybe_print_comment(item.span.lo)?;
565 self.print_outer_attributes(&item.attrs)?;
566 match item.node {
567 hir::ForeignItemFn(ref decl, ref generics) => {
568 self.head("")?;
569 self.print_fn(decl,
570 hir::Unsafety::Normal,
571 hir::Constness::NotConst,
572 Abi::Rust,
573 Some(item.name),
574 generics,
575 None,
576 &item.vis)?;
577 self.end()?; // end head-ibox
578 word(&mut self.s, ";")?;
579 self.end() // end the outer fn box
580 }
581 hir::ForeignItemStatic(ref t, m) => {
582 self.head(&visibility_qualified(&item.vis, "static"))?;
583 if m {
584 self.word_space("mut")?;
585 }
586 self.print_name(item.name)?;
587 self.word_space(":")?;
588 self.print_type(&t)?;
589 word(&mut self.s, ";")?;
590 self.end()?; // end the head-ibox
591 self.end() // end the outer cbox
592 }
593 }
594 }
595
596 fn print_associated_const(&mut self,
597 name: ast::Name,
598 ty: &hir::Ty,
599 default: Option<&hir::Expr>,
600 vis: &hir::Visibility)
601 -> io::Result<()> {
602 word(&mut self.s, &visibility_qualified(vis, ""))?;
603 self.word_space("const")?;
604 self.print_name(name)?;
605 self.word_space(":")?;
606 self.print_type(ty)?;
607 if let Some(expr) = default {
608 space(&mut self.s)?;
609 self.word_space("=")?;
610 self.print_expr(expr)?;
611 }
612 word(&mut self.s, ";")
613 }
614
615 fn print_associated_type(&mut self,
616 name: ast::Name,
617 bounds: Option<&hir::TyParamBounds>,
618 ty: Option<&hir::Ty>)
619 -> io::Result<()> {
620 self.word_space("type")?;
621 self.print_name(name)?;
622 if let Some(bounds) = bounds {
623 self.print_bounds(":", bounds)?;
624 }
625 if let Some(ty) = ty {
626 space(&mut self.s)?;
627 self.word_space("=")?;
628 self.print_type(ty)?;
629 }
630 word(&mut self.s, ";")
631 }
632
633 pub fn print_item_id(&mut self, item_id: &hir::ItemId) -> io::Result<()> {
634 if let Some(krate) = self.krate {
635 // skip nested items if krate context was not provided
636 let item = &krate.items[&item_id.id];
637 self.print_item(item)
638 } else {
639 Ok(())
640 }
641 }
642
643 /// Pretty-print an item
644 pub fn print_item(&mut self, item: &hir::Item) -> io::Result<()> {
645 self.hardbreak_if_not_bol()?;
646 self.maybe_print_comment(item.span.lo)?;
647 self.print_outer_attributes(&item.attrs)?;
648 self.ann.pre(self, NodeItem(item))?;
649 match item.node {
650 hir::ItemExternCrate(ref optional_path) => {
651 self.head(&visibility_qualified(&item.vis, "extern crate"))?;
652 if let Some(p) = *optional_path {
653 let val = p.as_str();
654 if val.contains("-") {
655 self.print_string(&val, ast::StrStyle::Cooked)?;
656 } else {
657 self.print_name(p)?;
658 }
659 space(&mut self.s)?;
660 word(&mut self.s, "as")?;
661 space(&mut self.s)?;
662 }
663 self.print_name(item.name)?;
664 word(&mut self.s, ";")?;
665 self.end()?; // end inner head-block
666 self.end()?; // end outer head-block
667 }
668 hir::ItemUse(ref vp) => {
669 self.head(&visibility_qualified(&item.vis, "use"))?;
670 self.print_view_path(&vp)?;
671 word(&mut self.s, ";")?;
672 self.end()?; // end inner head-block
673 self.end()?; // end outer head-block
674 }
675 hir::ItemStatic(ref ty, m, ref expr) => {
676 self.head(&visibility_qualified(&item.vis, "static"))?;
677 if m == hir::MutMutable {
678 self.word_space("mut")?;
679 }
680 self.print_name(item.name)?;
681 self.word_space(":")?;
682 self.print_type(&ty)?;
683 space(&mut self.s)?;
684 self.end()?; // end the head-ibox
685
686 self.word_space("=")?;
687 self.print_expr(&expr)?;
688 word(&mut self.s, ";")?;
689 self.end()?; // end the outer cbox
690 }
691 hir::ItemConst(ref ty, ref expr) => {
692 self.head(&visibility_qualified(&item.vis, "const"))?;
693 self.print_name(item.name)?;
694 self.word_space(":")?;
695 self.print_type(&ty)?;
696 space(&mut self.s)?;
697 self.end()?; // end the head-ibox
698
699 self.word_space("=")?;
700 self.print_expr(&expr)?;
701 word(&mut self.s, ";")?;
702 self.end()?; // end the outer cbox
703 }
704 hir::ItemFn(ref decl, unsafety, constness, abi, ref typarams, ref body) => {
705 self.head("")?;
706 self.print_fn(decl,
707 unsafety,
708 constness,
709 abi,
710 Some(item.name),
711 typarams,
712 None,
713 &item.vis)?;
714 word(&mut self.s, " ")?;
715 self.print_block_with_attrs(&body, &item.attrs)?;
716 }
717 hir::ItemMod(ref _mod) => {
718 self.head(&visibility_qualified(&item.vis, "mod"))?;
719 self.print_name(item.name)?;
720 self.nbsp()?;
721 self.bopen()?;
722 self.print_mod(_mod, &item.attrs)?;
723 self.bclose(item.span)?;
724 }
725 hir::ItemForeignMod(ref nmod) => {
726 self.head("extern")?;
727 self.word_nbsp(&nmod.abi.to_string())?;
728 self.bopen()?;
729 self.print_foreign_mod(nmod, &item.attrs)?;
730 self.bclose(item.span)?;
731 }
732 hir::ItemTy(ref ty, ref params) => {
733 self.ibox(indent_unit)?;
734 self.ibox(0)?;
735 self.word_nbsp(&visibility_qualified(&item.vis, "type"))?;
736 self.print_name(item.name)?;
737 self.print_generics(params)?;
738 self.end()?; // end the inner ibox
739
740 self.print_where_clause(&params.where_clause)?;
741 space(&mut self.s)?;
742 self.word_space("=")?;
743 self.print_type(&ty)?;
744 word(&mut self.s, ";")?;
745 self.end()?; // end the outer ibox
746 }
747 hir::ItemEnum(ref enum_definition, ref params) => {
748 self.print_enum_def(enum_definition, params, item.name, item.span, &item.vis)?;
749 }
750 hir::ItemStruct(ref struct_def, ref generics) => {
751 self.head(&visibility_qualified(&item.vis, "struct"))?;
752 self.print_struct(struct_def, generics, item.name, item.span, true)?;
753 }
754
755 hir::ItemDefaultImpl(unsafety, ref trait_ref) => {
756 self.head("")?;
757 self.print_visibility(&item.vis)?;
758 self.print_unsafety(unsafety)?;
759 self.word_nbsp("impl")?;
760 self.print_trait_ref(trait_ref)?;
761 space(&mut self.s)?;
762 self.word_space("for")?;
763 self.word_space("..")?;
764 self.bopen()?;
765 self.bclose(item.span)?;
766 }
767 hir::ItemImpl(unsafety,
768 polarity,
769 ref generics,
770 ref opt_trait,
771 ref ty,
772 ref impl_items) => {
773 self.head("")?;
774 self.print_visibility(&item.vis)?;
775 self.print_unsafety(unsafety)?;
776 self.word_nbsp("impl")?;
777
778 if generics.is_parameterized() {
779 self.print_generics(generics)?;
780 space(&mut self.s)?;
781 }
782
783 match polarity {
784 hir::ImplPolarity::Negative => {
785 word(&mut self.s, "!")?;
786 }
787 _ => {}
788 }
789
790 match opt_trait {
791 &Some(ref t) => {
792 self.print_trait_ref(t)?;
793 space(&mut self.s)?;
794 self.word_space("for")?;
795 }
796 &None => {}
797 }
798
799 self.print_type(&ty)?;
800 self.print_where_clause(&generics.where_clause)?;
801
802 space(&mut self.s)?;
803 self.bopen()?;
804 self.print_inner_attributes(&item.attrs)?;
805 for impl_item in impl_items {
806 self.print_impl_item(impl_item)?;
807 }
808 self.bclose(item.span)?;
809 }
810 hir::ItemTrait(unsafety, ref generics, ref bounds, ref trait_items) => {
811 self.head("")?;
812 self.print_visibility(&item.vis)?;
813 self.print_unsafety(unsafety)?;
814 self.word_nbsp("trait")?;
815 self.print_name(item.name)?;
816 self.print_generics(generics)?;
817 let mut real_bounds = Vec::with_capacity(bounds.len());
818 for b in bounds.iter() {
819 if let TraitTyParamBound(ref ptr, hir::TraitBoundModifier::Maybe) = *b {
820 space(&mut self.s)?;
821 self.word_space("for ?")?;
822 self.print_trait_ref(&ptr.trait_ref)?;
823 } else {
824 real_bounds.push(b.clone());
825 }
826 }
827 self.print_bounds(":", &real_bounds[..])?;
828 self.print_where_clause(&generics.where_clause)?;
829 word(&mut self.s, " ")?;
830 self.bopen()?;
831 for trait_item in trait_items {
832 self.print_trait_item(trait_item)?;
833 }
834 self.bclose(item.span)?;
835 }
836 }
837 self.ann.post(self, NodeItem(item))
838 }
839
840 fn print_trait_ref(&mut self, t: &hir::TraitRef) -> io::Result<()> {
841 self.print_path(&t.path, false, 0)
842 }
843
844 fn print_formal_lifetime_list(&mut self, lifetimes: &[hir::LifetimeDef]) -> io::Result<()> {
845 if !lifetimes.is_empty() {
846 word(&mut self.s, "for<")?;
847 let mut comma = false;
848 for lifetime_def in lifetimes {
849 if comma {
850 self.word_space(",")?
851 }
852 self.print_lifetime_def(lifetime_def)?;
853 comma = true;
854 }
855 word(&mut self.s, ">")?;
856 }
857 Ok(())
858 }
859
860 fn print_poly_trait_ref(&mut self, t: &hir::PolyTraitRef) -> io::Result<()> {
861 self.print_formal_lifetime_list(&t.bound_lifetimes)?;
862 self.print_trait_ref(&t.trait_ref)
863 }
864
865 pub fn print_enum_def(&mut self,
866 enum_definition: &hir::EnumDef,
867 generics: &hir::Generics,
868 name: ast::Name,
869 span: codemap::Span,
870 visibility: &hir::Visibility)
871 -> io::Result<()> {
872 self.head(&visibility_qualified(visibility, "enum"))?;
873 self.print_name(name)?;
874 self.print_generics(generics)?;
875 self.print_where_clause(&generics.where_clause)?;
876 space(&mut self.s)?;
877 self.print_variants(&enum_definition.variants, span)
878 }
879
880 pub fn print_variants(&mut self,
881 variants: &[hir::Variant],
882 span: codemap::Span)
883 -> io::Result<()> {
884 self.bopen()?;
885 for v in variants {
886 self.space_if_not_bol()?;
887 self.maybe_print_comment(v.span.lo)?;
888 self.print_outer_attributes(&v.node.attrs)?;
889 self.ibox(indent_unit)?;
890 self.print_variant(v)?;
891 word(&mut self.s, ",")?;
892 self.end()?;
893 self.maybe_print_trailing_comment(v.span, None)?;
894 }
895 self.bclose(span)
896 }
897
898 pub fn print_visibility(&mut self, vis: &hir::Visibility) -> io::Result<()> {
899 match *vis {
900 hir::Public => self.word_nbsp("pub"),
901 hir::Inherited => Ok(()),
902 }
903 }
904
905 pub fn print_struct(&mut self,
906 struct_def: &hir::VariantData,
907 generics: &hir::Generics,
908 name: ast::Name,
909 span: codemap::Span,
910 print_finalizer: bool)
911 -> io::Result<()> {
912 self.print_name(name)?;
913 self.print_generics(generics)?;
914 if !struct_def.is_struct() {
915 if struct_def.is_tuple() {
916 self.popen()?;
917 self.commasep(Inconsistent, struct_def.fields(), |s, field| {
918 s.print_visibility(&field.vis)?;
919 s.maybe_print_comment(field.span.lo)?;
920 s.print_type(&field.ty)
921 })?;
922 self.pclose()?;
923 }
924 self.print_where_clause(&generics.where_clause)?;
925 if print_finalizer {
926 word(&mut self.s, ";")?;
927 }
928 self.end()?;
929 self.end() // close the outer-box
930 } else {
931 self.print_where_clause(&generics.where_clause)?;
932 self.nbsp()?;
933 self.bopen()?;
934 self.hardbreak_if_not_bol()?;
935
936 for field in struct_def.fields() {
937 self.hardbreak_if_not_bol()?;
938 self.maybe_print_comment(field.span.lo)?;
939 self.print_outer_attributes(&field.attrs)?;
940 self.print_visibility(&field.vis)?;
941 self.print_name(field.name)?;
942 self.word_nbsp(":")?;
943 self.print_type(&field.ty)?;
944 word(&mut self.s, ",")?;
945 }
946
947 self.bclose(span)
948 }
949 }
950
951 pub fn print_variant(&mut self, v: &hir::Variant) -> io::Result<()> {
952 self.head("")?;
953 let generics = hir::Generics::empty();
954 self.print_struct(&v.node.data, &generics, v.node.name, v.span, false)?;
955 match v.node.disr_expr {
956 Some(ref d) => {
957 space(&mut self.s)?;
958 self.word_space("=")?;
959 self.print_expr(&d)
960 }
961 _ => Ok(()),
962 }
963 }
964 pub fn print_method_sig(&mut self,
965 name: ast::Name,
966 m: &hir::MethodSig,
967 vis: &hir::Visibility)
968 -> io::Result<()> {
969 self.print_fn(&m.decl,
970 m.unsafety,
971 m.constness,
972 m.abi,
973 Some(name),
974 &m.generics,
975 Some(&m.explicit_self.node),
976 vis)
977 }
978
979 pub fn print_trait_item(&mut self, ti: &hir::TraitItem) -> io::Result<()> {
980 self.ann.pre(self, NodeSubItem(ti.id))?;
981 self.hardbreak_if_not_bol()?;
982 self.maybe_print_comment(ti.span.lo)?;
983 self.print_outer_attributes(&ti.attrs)?;
984 match ti.node {
985 hir::ConstTraitItem(ref ty, ref default) => {
986 self.print_associated_const(ti.name,
987 &ty,
988 default.as_ref().map(|expr| &**expr),
989 &hir::Inherited)?;
990 }
991 hir::MethodTraitItem(ref sig, ref body) => {
992 if body.is_some() {
993 self.head("")?;
994 }
995 self.print_method_sig(ti.name, sig, &hir::Inherited)?;
996 if let Some(ref body) = *body {
997 self.nbsp()?;
998 self.print_block_with_attrs(body, &ti.attrs)?;
999 } else {
1000 word(&mut self.s, ";")?;
1001 }
1002 }
1003 hir::TypeTraitItem(ref bounds, ref default) => {
1004 self.print_associated_type(ti.name,
1005 Some(bounds),
1006 default.as_ref().map(|ty| &**ty))?;
1007 }
1008 }
1009 self.ann.post(self, NodeSubItem(ti.id))
1010 }
1011
1012 pub fn print_impl_item(&mut self, ii: &hir::ImplItem) -> io::Result<()> {
1013 self.ann.pre(self, NodeSubItem(ii.id))?;
1014 self.hardbreak_if_not_bol()?;
1015 self.maybe_print_comment(ii.span.lo)?;
1016 self.print_outer_attributes(&ii.attrs)?;
1017
1018 if let hir::Defaultness::Default = ii.defaultness {
1019 self.word_nbsp("default")?;
1020 }
1021
1022 match ii.node {
1023 hir::ImplItemKind::Const(ref ty, ref expr) => {
1024 self.print_associated_const(ii.name, &ty, Some(&expr), &ii.vis)?;
1025 }
1026 hir::ImplItemKind::Method(ref sig, ref body) => {
1027 self.head("")?;
1028 self.print_method_sig(ii.name, sig, &ii.vis)?;
1029 self.nbsp()?;
1030 self.print_block_with_attrs(body, &ii.attrs)?;
1031 }
1032 hir::ImplItemKind::Type(ref ty) => {
1033 self.print_associated_type(ii.name, None, Some(ty))?;
1034 }
1035 }
1036 self.ann.post(self, NodeSubItem(ii.id))
1037 }
1038
1039 pub fn print_stmt(&mut self, st: &hir::Stmt) -> io::Result<()> {
1040 self.maybe_print_comment(st.span.lo)?;
1041 match st.node {
1042 hir::StmtDecl(ref decl, _) => {
1043 self.print_decl(&decl)?;
1044 }
1045 hir::StmtExpr(ref expr, _) => {
1046 self.space_if_not_bol()?;
1047 self.print_expr(&expr)?;
1048 }
1049 hir::StmtSemi(ref expr, _) => {
1050 self.space_if_not_bol()?;
1051 self.print_expr(&expr)?;
1052 word(&mut self.s, ";")?;
1053 }
1054 }
1055 if stmt_ends_with_semi(&st.node) {
1056 word(&mut self.s, ";")?;
1057 }
1058 self.maybe_print_trailing_comment(st.span, None)
1059 }
1060
1061 pub fn print_block(&mut self, blk: &hir::Block) -> io::Result<()> {
1062 self.print_block_with_attrs(blk, &[])
1063 }
1064
1065 pub fn print_block_unclosed(&mut self, blk: &hir::Block) -> io::Result<()> {
1066 self.print_block_unclosed_indent(blk, indent_unit)
1067 }
1068
1069 pub fn print_block_unclosed_indent(&mut self,
1070 blk: &hir::Block,
1071 indented: usize)
1072 -> io::Result<()> {
1073 self.print_block_maybe_unclosed(blk, indented, &[], false)
1074 }
1075
1076 pub fn print_block_with_attrs(&mut self,
1077 blk: &hir::Block,
1078 attrs: &[ast::Attribute])
1079 -> io::Result<()> {
1080 self.print_block_maybe_unclosed(blk, indent_unit, attrs, true)
1081 }
1082
1083 pub fn print_block_maybe_unclosed(&mut self,
1084 blk: &hir::Block,
1085 indented: usize,
1086 attrs: &[ast::Attribute],
1087 close_box: bool)
1088 -> io::Result<()> {
1089 match blk.rules {
1090 hir::UnsafeBlock(..) => self.word_space("unsafe")?,
1091 hir::PushUnsafeBlock(..) => self.word_space("push_unsafe")?,
1092 hir::PopUnsafeBlock(..) => self.word_space("pop_unsafe")?,
1093 hir::PushUnstableBlock => self.word_space("push_unstable")?,
1094 hir::PopUnstableBlock => self.word_space("pop_unstable")?,
1095 hir::DefaultBlock => (),
1096 }
1097 self.maybe_print_comment(blk.span.lo)?;
1098 self.ann.pre(self, NodeBlock(blk))?;
1099 self.bopen()?;
1100
1101 self.print_inner_attributes(attrs)?;
1102
1103 for st in &blk.stmts {
1104 self.print_stmt(st)?;
1105 }
1106 match blk.expr {
1107 Some(ref expr) => {
1108 self.space_if_not_bol()?;
1109 self.print_expr(&expr)?;
1110 self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi))?;
1111 }
1112 _ => (),
1113 }
1114 self.bclose_maybe_open(blk.span, indented, close_box)?;
1115 self.ann.post(self, NodeBlock(blk))
1116 }
1117
1118 fn print_else(&mut self, els: Option<&hir::Expr>) -> io::Result<()> {
1119 match els {
1120 Some(_else) => {
1121 match _else.node {
1122 // "another else-if"
1123 hir::ExprIf(ref i, ref then, ref e) => {
1124 self.cbox(indent_unit - 1)?;
1125 self.ibox(0)?;
1126 word(&mut self.s, " else if ")?;
1127 self.print_expr(&i)?;
1128 space(&mut self.s)?;
1129 self.print_block(&then)?;
1130 self.print_else(e.as_ref().map(|e| &**e))
1131 }
1132 // "final else"
1133 hir::ExprBlock(ref b) => {
1134 self.cbox(indent_unit - 1)?;
1135 self.ibox(0)?;
1136 word(&mut self.s, " else ")?;
1137 self.print_block(&b)
1138 }
1139 // BLEAH, constraints would be great here
1140 _ => {
1141 panic!("print_if saw if with weird alternative");
1142 }
1143 }
1144 }
1145 _ => Ok(()),
1146 }
1147 }
1148
1149 pub fn print_if(&mut self,
1150 test: &hir::Expr,
1151 blk: &hir::Block,
1152 elseopt: Option<&hir::Expr>)
1153 -> io::Result<()> {
1154 self.head("if")?;
1155 self.print_expr(test)?;
1156 space(&mut self.s)?;
1157 self.print_block(blk)?;
1158 self.print_else(elseopt)
1159 }
1160
1161 pub fn print_if_let(&mut self,
1162 pat: &hir::Pat,
1163 expr: &hir::Expr,
1164 blk: &hir::Block,
1165 elseopt: Option<&hir::Expr>)
1166 -> io::Result<()> {
1167 self.head("if let")?;
1168 self.print_pat(pat)?;
1169 space(&mut self.s)?;
1170 self.word_space("=")?;
1171 self.print_expr(expr)?;
1172 space(&mut self.s)?;
1173 self.print_block(blk)?;
1174 self.print_else(elseopt)
1175 }
1176
1177
1178 fn print_call_post(&mut self, args: &[P<hir::Expr>]) -> io::Result<()> {
1179 self.popen()?;
1180 self.commasep_exprs(Inconsistent, args)?;
1181 self.pclose()
1182 }
1183
1184 pub fn print_expr_maybe_paren(&mut self, expr: &hir::Expr) -> io::Result<()> {
1185 let needs_par = needs_parentheses(expr);
1186 if needs_par {
1187 self.popen()?;
1188 }
1189 self.print_expr(expr)?;
1190 if needs_par {
1191 self.pclose()?;
1192 }
1193 Ok(())
1194 }
1195
1196 fn print_expr_vec(&mut self, exprs: &[P<hir::Expr>]) -> io::Result<()> {
1197 self.ibox(indent_unit)?;
1198 word(&mut self.s, "[")?;
1199 self.commasep_exprs(Inconsistent, &exprs[..])?;
1200 word(&mut self.s, "]")?;
1201 self.end()
1202 }
1203
1204 fn print_expr_repeat(&mut self, element: &hir::Expr, count: &hir::Expr) -> io::Result<()> {
1205 self.ibox(indent_unit)?;
1206 word(&mut self.s, "[")?;
1207 self.print_expr(element)?;
1208 self.word_space(";")?;
1209 self.print_expr(count)?;
1210 word(&mut self.s, "]")?;
1211 self.end()
1212 }
1213
1214 fn print_expr_struct(&mut self,
1215 path: &hir::Path,
1216 fields: &[hir::Field],
1217 wth: &Option<P<hir::Expr>>)
1218 -> io::Result<()> {
1219 self.print_path(path, true, 0)?;
1220 word(&mut self.s, "{")?;
1221 self.commasep_cmnt(Consistent,
1222 &fields[..],
1223 |s, field| {
1224 s.ibox(indent_unit)?;
1225 s.print_name(field.name.node)?;
1226 s.word_space(":")?;
1227 s.print_expr(&field.expr)?;
1228 s.end()
1229 },
1230 |f| f.span)?;
1231 match *wth {
1232 Some(ref expr) => {
1233 self.ibox(indent_unit)?;
1234 if !fields.is_empty() {
1235 word(&mut self.s, ",")?;
1236 space(&mut self.s)?;
1237 }
1238 word(&mut self.s, "..")?;
1239 self.print_expr(&expr)?;
1240 self.end()?;
1241 }
1242 _ => if !fields.is_empty() {
1243 word(&mut self.s, ",")?
1244 },
1245 }
1246 word(&mut self.s, "}")?;
1247 Ok(())
1248 }
1249
1250 fn print_expr_tup(&mut self, exprs: &[P<hir::Expr>]) -> io::Result<()> {
1251 self.popen()?;
1252 self.commasep_exprs(Inconsistent, &exprs[..])?;
1253 if exprs.len() == 1 {
1254 word(&mut self.s, ",")?;
1255 }
1256 self.pclose()
1257 }
1258
1259 fn print_expr_call(&mut self, func: &hir::Expr, args: &[P<hir::Expr>]) -> io::Result<()> {
1260 self.print_expr_maybe_paren(func)?;
1261 self.print_call_post(args)
1262 }
1263
1264 fn print_expr_method_call(&mut self,
1265 name: Spanned<ast::Name>,
1266 tys: &[P<hir::Ty>],
1267 args: &[P<hir::Expr>])
1268 -> io::Result<()> {
1269 let base_args = &args[1..];
1270 self.print_expr(&args[0])?;
1271 word(&mut self.s, ".")?;
1272 self.print_name(name.node)?;
1273 if !tys.is_empty() {
1274 word(&mut self.s, "::<")?;
1275 self.commasep(Inconsistent, tys, |s, ty| s.print_type(&ty))?;
1276 word(&mut self.s, ">")?;
1277 }
1278 self.print_call_post(base_args)
1279 }
1280
1281 fn print_expr_binary(&mut self,
1282 op: hir::BinOp,
1283 lhs: &hir::Expr,
1284 rhs: &hir::Expr)
1285 -> io::Result<()> {
1286 self.print_expr(lhs)?;
1287 space(&mut self.s)?;
1288 self.word_space(op.node.as_str())?;
1289 self.print_expr(rhs)
1290 }
1291
1292 fn print_expr_unary(&mut self, op: hir::UnOp, expr: &hir::Expr) -> io::Result<()> {
1293 word(&mut self.s, op.as_str())?;
1294 self.print_expr_maybe_paren(expr)
1295 }
1296
1297 fn print_expr_addr_of(&mut self,
1298 mutability: hir::Mutability,
1299 expr: &hir::Expr)
1300 -> io::Result<()> {
1301 word(&mut self.s, "&")?;
1302 self.print_mutability(mutability)?;
1303 self.print_expr_maybe_paren(expr)
1304 }
1305
1306 pub fn print_expr(&mut self, expr: &hir::Expr) -> io::Result<()> {
1307 self.maybe_print_comment(expr.span.lo)?;
1308 self.ibox(indent_unit)?;
1309 self.ann.pre(self, NodeExpr(expr))?;
1310 match expr.node {
1311 hir::ExprBox(ref expr) => {
1312 self.word_space("box")?;
1313 self.print_expr(expr)?;
1314 }
1315 hir::ExprVec(ref exprs) => {
1316 self.print_expr_vec(&exprs[..])?;
1317 }
1318 hir::ExprRepeat(ref element, ref count) => {
1319 self.print_expr_repeat(&element, &count)?;
1320 }
1321 hir::ExprStruct(ref path, ref fields, ref wth) => {
1322 self.print_expr_struct(path, &fields[..], wth)?;
1323 }
1324 hir::ExprTup(ref exprs) => {
1325 self.print_expr_tup(&exprs[..])?;
1326 }
1327 hir::ExprCall(ref func, ref args) => {
1328 self.print_expr_call(&func, &args[..])?;
1329 }
1330 hir::ExprMethodCall(name, ref tys, ref args) => {
1331 self.print_expr_method_call(name, &tys[..], &args[..])?;
1332 }
1333 hir::ExprBinary(op, ref lhs, ref rhs) => {
1334 self.print_expr_binary(op, &lhs, &rhs)?;
1335 }
1336 hir::ExprUnary(op, ref expr) => {
1337 self.print_expr_unary(op, &expr)?;
1338 }
1339 hir::ExprAddrOf(m, ref expr) => {
1340 self.print_expr_addr_of(m, &expr)?;
1341 }
1342 hir::ExprLit(ref lit) => {
1343 self.print_literal(&lit)?;
1344 }
1345 hir::ExprCast(ref expr, ref ty) => {
1346 self.print_expr(&expr)?;
1347 space(&mut self.s)?;
1348 self.word_space("as")?;
1349 self.print_type(&ty)?;
1350 }
1351 hir::ExprType(ref expr, ref ty) => {
1352 self.print_expr(&expr)?;
1353 self.word_space(":")?;
1354 self.print_type(&ty)?;
1355 }
1356 hir::ExprIf(ref test, ref blk, ref elseopt) => {
1357 self.print_if(&test, &blk, elseopt.as_ref().map(|e| &**e))?;
1358 }
1359 hir::ExprWhile(ref test, ref blk, opt_ident) => {
1360 if let Some(ident) = opt_ident {
1361 self.print_name(ident.name)?;
1362 self.word_space(":")?;
1363 }
1364 self.head("while")?;
1365 self.print_expr(&test)?;
1366 space(&mut self.s)?;
1367 self.print_block(&blk)?;
1368 }
1369 hir::ExprLoop(ref blk, opt_ident) => {
1370 if let Some(ident) = opt_ident {
1371 self.print_name(ident.name)?;
1372 self.word_space(":")?;
1373 }
1374 self.head("loop")?;
1375 space(&mut self.s)?;
1376 self.print_block(&blk)?;
1377 }
1378 hir::ExprMatch(ref expr, ref arms, _) => {
1379 self.cbox(indent_unit)?;
1380 self.ibox(4)?;
1381 self.word_nbsp("match")?;
1382 self.print_expr(&expr)?;
1383 space(&mut self.s)?;
1384 self.bopen()?;
1385 for arm in arms {
1386 self.print_arm(arm)?;
1387 }
1388 self.bclose_(expr.span, indent_unit)?;
1389 }
1390 hir::ExprClosure(capture_clause, ref decl, ref body) => {
1391 self.print_capture_clause(capture_clause)?;
1392
1393 self.print_fn_block_args(&decl)?;
1394 space(&mut self.s)?;
1395
1396 let default_return = match decl.output {
1397 hir::DefaultReturn(..) => true,
1398 _ => false,
1399 };
1400
1401 if !default_return || !body.stmts.is_empty() || body.expr.is_none() {
1402 self.print_block_unclosed(&body)?;
1403 } else {
1404 // we extract the block, so as not to create another set of boxes
1405 match body.expr.as_ref().unwrap().node {
1406 hir::ExprBlock(ref blk) => {
1407 self.print_block_unclosed(&blk)?;
1408 }
1409 _ => {
1410 // this is a bare expression
1411 self.print_expr(body.expr.as_ref().map(|e| &**e).unwrap())?;
1412 self.end()?; // need to close a box
1413 }
1414 }
1415 }
1416 // a box will be closed by print_expr, but we didn't want an overall
1417 // wrapper so we closed the corresponding opening. so create an
1418 // empty box to satisfy the close.
1419 self.ibox(0)?;
1420 }
1421 hir::ExprBlock(ref blk) => {
1422 // containing cbox, will be closed by print-block at }
1423 self.cbox(indent_unit)?;
1424 // head-box, will be closed by print-block after {
1425 self.ibox(0)?;
1426 self.print_block(&blk)?;
1427 }
1428 hir::ExprAssign(ref lhs, ref rhs) => {
1429 self.print_expr(&lhs)?;
1430 space(&mut self.s)?;
1431 self.word_space("=")?;
1432 self.print_expr(&rhs)?;
1433 }
1434 hir::ExprAssignOp(op, ref lhs, ref rhs) => {
1435 self.print_expr(&lhs)?;
1436 space(&mut self.s)?;
1437 word(&mut self.s, op.node.as_str())?;
1438 self.word_space("=")?;
1439 self.print_expr(&rhs)?;
1440 }
1441 hir::ExprField(ref expr, name) => {
1442 self.print_expr(&expr)?;
1443 word(&mut self.s, ".")?;
1444 self.print_name(name.node)?;
1445 }
1446 hir::ExprTupField(ref expr, id) => {
1447 self.print_expr(&expr)?;
1448 word(&mut self.s, ".")?;
1449 self.print_usize(id.node)?;
1450 }
1451 hir::ExprIndex(ref expr, ref index) => {
1452 self.print_expr(&expr)?;
1453 word(&mut self.s, "[")?;
1454 self.print_expr(&index)?;
1455 word(&mut self.s, "]")?;
1456 }
1457 hir::ExprPath(None, ref path) => {
1458 self.print_path(path, true, 0)?
1459 }
1460 hir::ExprPath(Some(ref qself), ref path) => {
1461 self.print_qpath(path, qself, true)?
1462 }
1463 hir::ExprBreak(opt_ident) => {
1464 word(&mut self.s, "break")?;
1465 space(&mut self.s)?;
1466 if let Some(ident) = opt_ident {
1467 self.print_name(ident.node.name)?;
1468 space(&mut self.s)?;
1469 }
1470 }
1471 hir::ExprAgain(opt_ident) => {
1472 word(&mut self.s, "continue")?;
1473 space(&mut self.s)?;
1474 if let Some(ident) = opt_ident {
1475 self.print_name(ident.node.name)?;
1476 space(&mut self.s)?
1477 }
1478 }
1479 hir::ExprRet(ref result) => {
1480 word(&mut self.s, "return")?;
1481 match *result {
1482 Some(ref expr) => {
1483 word(&mut self.s, " ")?;
1484 self.print_expr(&expr)?;
1485 }
1486 _ => (),
1487 }
1488 }
1489 hir::ExprInlineAsm(ref a, ref outputs, ref inputs) => {
1490 word(&mut self.s, "asm!")?;
1491 self.popen()?;
1492 self.print_string(&a.asm, a.asm_str_style)?;
1493 self.word_space(":")?;
1494
1495 let mut out_idx = 0;
1496 self.commasep(Inconsistent, &a.outputs, |s, out| {
1497 let mut ch = out.constraint.chars();
1498 match ch.next() {
1499 Some('=') if out.is_rw => {
1500 s.print_string(&format!("+{}", ch.as_str()),
1501 ast::StrStyle::Cooked)?
1502 }
1503 _ => s.print_string(&out.constraint,
1504 ast::StrStyle::Cooked)?,
1505 }
1506 s.popen()?;
1507 s.print_expr(&outputs[out_idx])?;
1508 s.pclose()?;
1509 out_idx += 1;
1510 Ok(())
1511 })?;
1512 space(&mut self.s)?;
1513 self.word_space(":")?;
1514
1515 let mut in_idx = 0;
1516 self.commasep(Inconsistent, &a.inputs, |s, co| {
1517 s.print_string(&co, ast::StrStyle::Cooked)?;
1518 s.popen()?;
1519 s.print_expr(&inputs[in_idx])?;
1520 s.pclose()?;
1521 in_idx += 1;
1522 Ok(())
1523 })?;
1524 space(&mut self.s)?;
1525 self.word_space(":")?;
1526
1527 self.commasep(Inconsistent, &a.clobbers, |s, co| {
1528 s.print_string(&co, ast::StrStyle::Cooked)?;
1529 Ok(())
1530 })?;
1531
1532 let mut options = vec![];
1533 if a.volatile {
1534 options.push("volatile");
1535 }
1536 if a.alignstack {
1537 options.push("alignstack");
1538 }
1539 if a.dialect == ast::AsmDialect::Intel {
1540 options.push("intel");
1541 }
1542
1543 if !options.is_empty() {
1544 space(&mut self.s)?;
1545 self.word_space(":")?;
1546 self.commasep(Inconsistent, &options, |s, &co| {
1547 s.print_string(co, ast::StrStyle::Cooked)?;
1548 Ok(())
1549 })?;
1550 }
1551
1552 self.pclose()?;
1553 }
1554 }
1555 self.ann.post(self, NodeExpr(expr))?;
1556 self.end()
1557 }
1558
1559 pub fn print_local_decl(&mut self, loc: &hir::Local) -> io::Result<()> {
1560 self.print_pat(&loc.pat)?;
1561 if let Some(ref ty) = loc.ty {
1562 self.word_space(":")?;
1563 self.print_type(&ty)?;
1564 }
1565 Ok(())
1566 }
1567
1568 pub fn print_decl(&mut self, decl: &hir::Decl) -> io::Result<()> {
1569 self.maybe_print_comment(decl.span.lo)?;
1570 match decl.node {
1571 hir::DeclLocal(ref loc) => {
1572 self.space_if_not_bol()?;
1573 self.ibox(indent_unit)?;
1574 self.word_nbsp("let")?;
1575
1576 self.ibox(indent_unit)?;
1577 self.print_local_decl(&loc)?;
1578 self.end()?;
1579 if let Some(ref init) = loc.init {
1580 self.nbsp()?;
1581 self.word_space("=")?;
1582 self.print_expr(&init)?;
1583 }
1584 self.end()
1585 }
1586 hir::DeclItem(ref item) => {
1587 self.print_item_id(item)
1588 }
1589 }
1590 }
1591
1592 pub fn print_usize(&mut self, i: usize) -> io::Result<()> {
1593 word(&mut self.s, &i.to_string())
1594 }
1595
1596 pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
1597 word(&mut self.s, &name.as_str())?;
1598 self.ann.post(self, NodeName(&name))
1599 }
1600
1601 pub fn print_for_decl(&mut self, loc: &hir::Local, coll: &hir::Expr) -> io::Result<()> {
1602 self.print_local_decl(loc)?;
1603 space(&mut self.s)?;
1604 self.word_space("in")?;
1605 self.print_expr(coll)
1606 }
1607
1608 fn print_path(&mut self,
1609 path: &hir::Path,
1610 colons_before_params: bool,
1611 depth: usize)
1612 -> io::Result<()> {
1613 self.maybe_print_comment(path.span.lo)?;
1614
1615 let mut first = !path.global;
1616 for segment in &path.segments[..path.segments.len() - depth] {
1617 if first {
1618 first = false
1619 } else {
1620 word(&mut self.s, "::")?
1621 }
1622
1623 self.print_name(segment.identifier.name)?;
1624
1625 self.print_path_parameters(&segment.parameters, colons_before_params)?;
1626 }
1627
1628 Ok(())
1629 }
1630
1631 fn print_qpath(&mut self,
1632 path: &hir::Path,
1633 qself: &hir::QSelf,
1634 colons_before_params: bool)
1635 -> io::Result<()> {
1636 word(&mut self.s, "<")?;
1637 self.print_type(&qself.ty)?;
1638 if qself.position > 0 {
1639 space(&mut self.s)?;
1640 self.word_space("as")?;
1641 let depth = path.segments.len() - qself.position;
1642 self.print_path(&path, false, depth)?;
1643 }
1644 word(&mut self.s, ">")?;
1645 word(&mut self.s, "::")?;
1646 let item_segment = path.segments.last().unwrap();
1647 self.print_name(item_segment.identifier.name)?;
1648 self.print_path_parameters(&item_segment.parameters, colons_before_params)
1649 }
1650
1651 fn print_path_parameters(&mut self,
1652 parameters: &hir::PathParameters,
1653 colons_before_params: bool)
1654 -> io::Result<()> {
1655 if parameters.is_empty() {
1656 return Ok(());
1657 }
1658
1659 if colons_before_params {
1660 word(&mut self.s, "::")?
1661 }
1662
1663 match *parameters {
1664 hir::AngleBracketedParameters(ref data) => {
1665 word(&mut self.s, "<")?;
1666
1667 let mut comma = false;
1668 for lifetime in &data.lifetimes {
1669 if comma {
1670 self.word_space(",")?
1671 }
1672 self.print_lifetime(lifetime)?;
1673 comma = true;
1674 }
1675
1676 if !data.types.is_empty() {
1677 if comma {
1678 self.word_space(",")?
1679 }
1680 self.commasep(Inconsistent, &data.types, |s, ty| s.print_type(&ty))?;
1681 comma = true;
1682 }
1683
1684 for binding in data.bindings.iter() {
1685 if comma {
1686 self.word_space(",")?
1687 }
1688 self.print_name(binding.name)?;
1689 space(&mut self.s)?;
1690 self.word_space("=")?;
1691 self.print_type(&binding.ty)?;
1692 comma = true;
1693 }
1694
1695 word(&mut self.s, ">")?
1696 }
1697
1698 hir::ParenthesizedParameters(ref data) => {
1699 word(&mut self.s, "(")?;
1700 self.commasep(Inconsistent, &data.inputs, |s, ty| s.print_type(&ty))?;
1701 word(&mut self.s, ")")?;
1702
1703 match data.output {
1704 None => {}
1705 Some(ref ty) => {
1706 self.space_if_not_bol()?;
1707 self.word_space("->")?;
1708 self.print_type(&ty)?;
1709 }
1710 }
1711 }
1712 }
1713
1714 Ok(())
1715 }
1716
1717 pub fn print_pat(&mut self, pat: &hir::Pat) -> io::Result<()> {
1718 self.maybe_print_comment(pat.span.lo)?;
1719 self.ann.pre(self, NodePat(pat))?;
1720 // Pat isn't normalized, but the beauty of it
1721 // is that it doesn't matter
1722 match pat.node {
1723 PatKind::Wild => word(&mut self.s, "_")?,
1724 PatKind::Ident(binding_mode, ref path1, ref sub) => {
1725 match binding_mode {
1726 hir::BindByRef(mutbl) => {
1727 self.word_nbsp("ref")?;
1728 self.print_mutability(mutbl)?;
1729 }
1730 hir::BindByValue(hir::MutImmutable) => {}
1731 hir::BindByValue(hir::MutMutable) => {
1732 self.word_nbsp("mut")?;
1733 }
1734 }
1735 self.print_name(path1.node.name)?;
1736 match *sub {
1737 Some(ref p) => {
1738 word(&mut self.s, "@")?;
1739 self.print_pat(&p)?;
1740 }
1741 None => (),
1742 }
1743 }
1744 PatKind::TupleStruct(ref path, ref args_) => {
1745 self.print_path(path, true, 0)?;
1746 match *args_ {
1747 None => word(&mut self.s, "(..)")?,
1748 Some(ref args) => {
1749 self.popen()?;
1750 self.commasep(Inconsistent, &args[..], |s, p| s.print_pat(&p))?;
1751 self.pclose()?;
1752 }
1753 }
1754 }
1755 PatKind::Path(ref path) => {
1756 self.print_path(path, true, 0)?;
1757 }
1758 PatKind::QPath(ref qself, ref path) => {
1759 self.print_qpath(path, qself, false)?;
1760 }
1761 PatKind::Struct(ref path, ref fields, etc) => {
1762 self.print_path(path, true, 0)?;
1763 self.nbsp()?;
1764 self.word_space("{")?;
1765 self.commasep_cmnt(Consistent,
1766 &fields[..],
1767 |s, f| {
1768 s.cbox(indent_unit)?;
1769 if !f.node.is_shorthand {
1770 s.print_name(f.node.name)?;
1771 s.word_nbsp(":")?;
1772 }
1773 s.print_pat(&f.node.pat)?;
1774 s.end()
1775 },
1776 |f| f.node.pat.span)?;
1777 if etc {
1778 if !fields.is_empty() {
1779 self.word_space(",")?;
1780 }
1781 word(&mut self.s, "..")?;
1782 }
1783 space(&mut self.s)?;
1784 word(&mut self.s, "}")?;
1785 }
1786 PatKind::Tup(ref elts) => {
1787 self.popen()?;
1788 self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(&p))?;
1789 if elts.len() == 1 {
1790 word(&mut self.s, ",")?;
1791 }
1792 self.pclose()?;
1793 }
1794 PatKind::Box(ref inner) => {
1795 word(&mut self.s, "box ")?;
1796 self.print_pat(&inner)?;
1797 }
1798 PatKind::Ref(ref inner, mutbl) => {
1799 word(&mut self.s, "&")?;
1800 if mutbl == hir::MutMutable {
1801 word(&mut self.s, "mut ")?;
1802 }
1803 self.print_pat(&inner)?;
1804 }
1805 PatKind::Lit(ref e) => self.print_expr(&e)?,
1806 PatKind::Range(ref begin, ref end) => {
1807 self.print_expr(&begin)?;
1808 space(&mut self.s)?;
1809 word(&mut self.s, "...")?;
1810 self.print_expr(&end)?;
1811 }
1812 PatKind::Vec(ref before, ref slice, ref after) => {
1813 word(&mut self.s, "[")?;
1814 self.commasep(Inconsistent, &before[..], |s, p| s.print_pat(&p))?;
1815 if let Some(ref p) = *slice {
1816 if !before.is_empty() {
1817 self.word_space(",")?;
1818 }
1819 if p.node != PatKind::Wild {
1820 self.print_pat(&p)?;
1821 }
1822 word(&mut self.s, "..")?;
1823 if !after.is_empty() {
1824 self.word_space(",")?;
1825 }
1826 }
1827 self.commasep(Inconsistent, &after[..], |s, p| s.print_pat(&p))?;
1828 word(&mut self.s, "]")?;
1829 }
1830 }
1831 self.ann.post(self, NodePat(pat))
1832 }
1833
1834 fn print_arm(&mut self, arm: &hir::Arm) -> io::Result<()> {
1835 // I have no idea why this check is necessary, but here it
1836 // is :(
1837 if arm.attrs.is_empty() {
1838 space(&mut self.s)?;
1839 }
1840 self.cbox(indent_unit)?;
1841 self.ibox(0)?;
1842 self.print_outer_attributes(&arm.attrs)?;
1843 let mut first = true;
1844 for p in &arm.pats {
1845 if first {
1846 first = false;
1847 } else {
1848 space(&mut self.s)?;
1849 self.word_space("|")?;
1850 }
1851 self.print_pat(&p)?;
1852 }
1853 space(&mut self.s)?;
1854 if let Some(ref e) = arm.guard {
1855 self.word_space("if")?;
1856 self.print_expr(&e)?;
1857 space(&mut self.s)?;
1858 }
1859 self.word_space("=>")?;
1860
1861 match arm.body.node {
1862 hir::ExprBlock(ref blk) => {
1863 // the block will close the pattern's ibox
1864 self.print_block_unclosed_indent(&blk, indent_unit)?;
1865
1866 // If it is a user-provided unsafe block, print a comma after it
1867 if let hir::UnsafeBlock(hir::UserProvided) = blk.rules {
1868 word(&mut self.s, ",")?;
1869 }
1870 }
1871 _ => {
1872 self.end()?; // close the ibox for the pattern
1873 self.print_expr(&arm.body)?;
1874 word(&mut self.s, ",")?;
1875 }
1876 }
1877 self.end() // close enclosing cbox
1878 }
1879
1880 // Returns whether it printed anything
1881 fn print_explicit_self(&mut self,
1882 explicit_self: &hir::ExplicitSelf_,
1883 mutbl: hir::Mutability)
1884 -> io::Result<bool> {
1885 self.print_mutability(mutbl)?;
1886 match *explicit_self {
1887 hir::SelfStatic => {
1888 return Ok(false);
1889 }
1890 hir::SelfValue(_) => {
1891 word(&mut self.s, "self")?;
1892 }
1893 hir::SelfRegion(ref lt, m, _) => {
1894 word(&mut self.s, "&")?;
1895 self.print_opt_lifetime(lt)?;
1896 self.print_mutability(m)?;
1897 word(&mut self.s, "self")?;
1898 }
1899 hir::SelfExplicit(ref typ, _) => {
1900 word(&mut self.s, "self")?;
1901 self.word_space(":")?;
1902 self.print_type(&typ)?;
1903 }
1904 }
1905 return Ok(true);
1906 }
1907
1908 pub fn print_fn(&mut self,
1909 decl: &hir::FnDecl,
1910 unsafety: hir::Unsafety,
1911 constness: hir::Constness,
1912 abi: Abi,
1913 name: Option<ast::Name>,
1914 generics: &hir::Generics,
1915 opt_explicit_self: Option<&hir::ExplicitSelf_>,
1916 vis: &hir::Visibility)
1917 -> io::Result<()> {
1918 self.print_fn_header_info(unsafety, constness, abi, vis)?;
1919
1920 if let Some(name) = name {
1921 self.nbsp()?;
1922 self.print_name(name)?;
1923 }
1924 self.print_generics(generics)?;
1925 self.print_fn_args_and_ret(decl, opt_explicit_self)?;
1926 self.print_where_clause(&generics.where_clause)
1927 }
1928
1929 pub fn print_fn_args(&mut self,
1930 decl: &hir::FnDecl,
1931 opt_explicit_self: Option<&hir::ExplicitSelf_>,
1932 is_closure: bool)
1933 -> io::Result<()> {
1934 // It is unfortunate to duplicate the commasep logic, but we want the
1935 // self type and the args all in the same box.
1936 self.rbox(0, Inconsistent)?;
1937 let mut first = true;
1938 if let Some(explicit_self) = opt_explicit_self {
1939 let m = match explicit_self {
1940 &hir::SelfStatic => hir::MutImmutable,
1941 _ => match decl.inputs[0].pat.node {
1942 PatKind::Ident(hir::BindByValue(m), _, _) => m,
1943 _ => hir::MutImmutable,
1944 },
1945 };
1946 first = !self.print_explicit_self(explicit_self, m)?;
1947 }
1948
1949 // HACK(eddyb) ignore the separately printed self argument.
1950 let args = if first {
1951 &decl.inputs[..]
1952 } else {
1953 &decl.inputs[1..]
1954 };
1955
1956 for arg in args {
1957 if first {
1958 first = false;
1959 } else {
1960 self.word_space(",")?;
1961 }
1962 self.print_arg(arg, is_closure)?;
1963 }
1964
1965 self.end()
1966 }
1967
1968 pub fn print_fn_args_and_ret(&mut self,
1969 decl: &hir::FnDecl,
1970 opt_explicit_self: Option<&hir::ExplicitSelf_>)
1971 -> io::Result<()> {
1972 self.popen()?;
1973 self.print_fn_args(decl, opt_explicit_self, false)?;
1974 if decl.variadic {
1975 word(&mut self.s, ", ...")?;
1976 }
1977 self.pclose()?;
1978
1979 self.print_fn_output(decl)
1980 }
1981
1982 pub fn print_fn_block_args(&mut self, decl: &hir::FnDecl) -> io::Result<()> {
1983 word(&mut self.s, "|")?;
1984 self.print_fn_args(decl, None, true)?;
1985 word(&mut self.s, "|")?;
1986
1987 if let hir::DefaultReturn(..) = decl.output {
1988 return Ok(());
1989 }
1990
1991 self.space_if_not_bol()?;
1992 self.word_space("->")?;
1993 match decl.output {
1994 hir::Return(ref ty) => {
1995 self.print_type(&ty)?;
1996 self.maybe_print_comment(ty.span.lo)
1997 }
1998 hir::DefaultReturn(..) => unreachable!(),
1999 hir::NoReturn(span) => {
2000 self.word_nbsp("!")?;
2001 self.maybe_print_comment(span.lo)
2002 }
2003 }
2004 }
2005
2006 pub fn print_capture_clause(&mut self, capture_clause: hir::CaptureClause) -> io::Result<()> {
2007 match capture_clause {
2008 hir::CaptureByValue => self.word_space("move"),
2009 hir::CaptureByRef => Ok(()),
2010 }
2011 }
2012
2013 pub fn print_bounds(&mut self, prefix: &str, bounds: &[hir::TyParamBound]) -> io::Result<()> {
2014 if !bounds.is_empty() {
2015 word(&mut self.s, prefix)?;
2016 let mut first = true;
2017 for bound in bounds {
2018 self.nbsp()?;
2019 if first {
2020 first = false;
2021 } else {
2022 self.word_space("+")?;
2023 }
2024
2025 match *bound {
2026 TraitTyParamBound(ref tref, TraitBoundModifier::None) => {
2027 self.print_poly_trait_ref(tref)
2028 }
2029 TraitTyParamBound(ref tref, TraitBoundModifier::Maybe) => {
2030 word(&mut self.s, "?")?;
2031 self.print_poly_trait_ref(tref)
2032 }
2033 RegionTyParamBound(ref lt) => {
2034 self.print_lifetime(lt)
2035 }
2036 }?
2037 }
2038 Ok(())
2039 } else {
2040 Ok(())
2041 }
2042 }
2043
2044 pub fn print_lifetime(&mut self, lifetime: &hir::Lifetime) -> io::Result<()> {
2045 self.print_name(lifetime.name)
2046 }
2047
2048 pub fn print_lifetime_def(&mut self, lifetime: &hir::LifetimeDef) -> io::Result<()> {
2049 self.print_lifetime(&lifetime.lifetime)?;
2050 let mut sep = ":";
2051 for v in &lifetime.bounds {
2052 word(&mut self.s, sep)?;
2053 self.print_lifetime(v)?;
2054 sep = "+";
2055 }
2056 Ok(())
2057 }
2058
2059 pub fn print_generics(&mut self, generics: &hir::Generics) -> io::Result<()> {
2060 let total = generics.lifetimes.len() + generics.ty_params.len();
2061 if total == 0 {
2062 return Ok(());
2063 }
2064
2065 word(&mut self.s, "<")?;
2066
2067 let mut ints = Vec::new();
2068 for i in 0..total {
2069 ints.push(i);
2070 }
2071
2072 self.commasep(Inconsistent, &ints[..], |s, &idx| {
2073 if idx < generics.lifetimes.len() {
2074 let lifetime = &generics.lifetimes[idx];
2075 s.print_lifetime_def(lifetime)
2076 } else {
2077 let idx = idx - generics.lifetimes.len();
2078 let param = &generics.ty_params[idx];
2079 s.print_ty_param(param)
2080 }
2081 })?;
2082
2083 word(&mut self.s, ">")?;
2084 Ok(())
2085 }
2086
2087 pub fn print_ty_param(&mut self, param: &hir::TyParam) -> io::Result<()> {
2088 self.print_name(param.name)?;
2089 self.print_bounds(":", &param.bounds)?;
2090 match param.default {
2091 Some(ref default) => {
2092 space(&mut self.s)?;
2093 self.word_space("=")?;
2094 self.print_type(&default)
2095 }
2096 _ => Ok(()),
2097 }
2098 }
2099
2100 pub fn print_where_clause(&mut self, where_clause: &hir::WhereClause) -> io::Result<()> {
2101 if where_clause.predicates.is_empty() {
2102 return Ok(());
2103 }
2104
2105 space(&mut self.s)?;
2106 self.word_space("where")?;
2107
2108 for (i, predicate) in where_clause.predicates.iter().enumerate() {
2109 if i != 0 {
2110 self.word_space(",")?;
2111 }
2112
2113 match predicate {
2114 &hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate{ref bound_lifetimes,
2115 ref bounded_ty,
2116 ref bounds,
2117 ..}) => {
2118 self.print_formal_lifetime_list(bound_lifetimes)?;
2119 self.print_type(&bounded_ty)?;
2120 self.print_bounds(":", bounds)?;
2121 }
2122 &hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate{ref lifetime,
2123 ref bounds,
2124 ..}) => {
2125 self.print_lifetime(lifetime)?;
2126 word(&mut self.s, ":")?;
2127
2128 for (i, bound) in bounds.iter().enumerate() {
2129 self.print_lifetime(bound)?;
2130
2131 if i != 0 {
2132 word(&mut self.s, ":")?;
2133 }
2134 }
2135 }
2136 &hir::WherePredicate::EqPredicate(hir::WhereEqPredicate{ref path, ref ty, ..}) => {
2137 self.print_path(path, false, 0)?;
2138 space(&mut self.s)?;
2139 self.word_space("=")?;
2140 self.print_type(&ty)?;
2141 }
2142 }
2143 }
2144
2145 Ok(())
2146 }
2147
2148 pub fn print_view_path(&mut self, vp: &hir::ViewPath) -> io::Result<()> {
2149 match vp.node {
2150 hir::ViewPathSimple(name, ref path) => {
2151 self.print_path(path, false, 0)?;
2152
2153 if path.segments.last().unwrap().identifier.name != name {
2154 space(&mut self.s)?;
2155 self.word_space("as")?;
2156 self.print_name(name)?;
2157 }
2158
2159 Ok(())
2160 }
2161
2162 hir::ViewPathGlob(ref path) => {
2163 self.print_path(path, false, 0)?;
2164 word(&mut self.s, "::*")
2165 }
2166
2167 hir::ViewPathList(ref path, ref segments) => {
2168 if path.segments.is_empty() {
2169 word(&mut self.s, "{")?;
2170 } else {
2171 self.print_path(path, false, 0)?;
2172 word(&mut self.s, "::{")?;
2173 }
2174 self.commasep(Inconsistent, &segments[..], |s, w| {
2175 match w.node {
2176 hir::PathListIdent { name, .. } => {
2177 s.print_name(name)
2178 }
2179 hir::PathListMod { .. } => {
2180 word(&mut s.s, "self")
2181 }
2182 }
2183 })?;
2184 word(&mut self.s, "}")
2185 }
2186 }
2187 }
2188
2189 pub fn print_mutability(&mut self, mutbl: hir::Mutability) -> io::Result<()> {
2190 match mutbl {
2191 hir::MutMutable => self.word_nbsp("mut"),
2192 hir::MutImmutable => Ok(()),
2193 }
2194 }
2195
2196 pub fn print_mt(&mut self, mt: &hir::MutTy) -> io::Result<()> {
2197 self.print_mutability(mt.mutbl)?;
2198 self.print_type(&mt.ty)
2199 }
2200
2201 pub fn print_arg(&mut self, input: &hir::Arg, is_closure: bool) -> io::Result<()> {
2202 self.ibox(indent_unit)?;
2203 match input.ty.node {
2204 hir::TyInfer if is_closure => self.print_pat(&input.pat)?,
2205 _ => {
2206 match input.pat.node {
2207 PatKind::Ident(_, ref path1, _) if
2208 path1.node.name ==
2209 parse::token::special_idents::invalid.name => {
2210 // Do nothing.
2211 }
2212 _ => {
2213 self.print_pat(&input.pat)?;
2214 word(&mut self.s, ":")?;
2215 space(&mut self.s)?;
2216 }
2217 }
2218 self.print_type(&input.ty)?;
2219 }
2220 }
2221 self.end()
2222 }
2223
2224 pub fn print_fn_output(&mut self, decl: &hir::FnDecl) -> io::Result<()> {
2225 if let hir::DefaultReturn(..) = decl.output {
2226 return Ok(());
2227 }
2228
2229 self.space_if_not_bol()?;
2230 self.ibox(indent_unit)?;
2231 self.word_space("->")?;
2232 match decl.output {
2233 hir::NoReturn(_) => self.word_nbsp("!")?,
2234 hir::DefaultReturn(..) => unreachable!(),
2235 hir::Return(ref ty) => self.print_type(&ty)?,
2236 }
2237 self.end()?;
2238
2239 match decl.output {
2240 hir::Return(ref output) => self.maybe_print_comment(output.span.lo),
2241 _ => Ok(()),
2242 }
2243 }
2244
2245 pub fn print_ty_fn(&mut self,
2246 abi: Abi,
2247 unsafety: hir::Unsafety,
2248 decl: &hir::FnDecl,
2249 name: Option<ast::Name>,
2250 generics: &hir::Generics,
2251 opt_explicit_self: Option<&hir::ExplicitSelf_>)
2252 -> io::Result<()> {
2253 self.ibox(indent_unit)?;
2254 if !generics.lifetimes.is_empty() || !generics.ty_params.is_empty() {
2255 word(&mut self.s, "for")?;
2256 self.print_generics(generics)?;
2257 }
2258 let generics = hir::Generics {
2259 lifetimes: hir::HirVec::new(),
2260 ty_params: hir::HirVec::new(),
2261 where_clause: hir::WhereClause {
2262 id: ast::DUMMY_NODE_ID,
2263 predicates: hir::HirVec::new(),
2264 },
2265 };
2266 self.print_fn(decl,
2267 unsafety,
2268 hir::Constness::NotConst,
2269 abi,
2270 name,
2271 &generics,
2272 opt_explicit_self,
2273 &hir::Inherited)?;
2274 self.end()
2275 }
2276
2277 pub fn maybe_print_trailing_comment(&mut self,
2278 span: codemap::Span,
2279 next_pos: Option<BytePos>)
2280 -> io::Result<()> {
2281 let cm = match self.cm {
2282 Some(cm) => cm,
2283 _ => return Ok(()),
2284 };
2285 match self.next_comment() {
2286 Some(ref cmnt) => {
2287 if (*cmnt).style != comments::Trailing {
2288 return Ok(());
2289 }
2290 let span_line = cm.lookup_char_pos(span.hi);
2291 let comment_line = cm.lookup_char_pos((*cmnt).pos);
2292 let mut next = (*cmnt).pos + BytePos(1);
2293 match next_pos {
2294 None => (),
2295 Some(p) => next = p,
2296 }
2297 if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
2298 span_line.line == comment_line.line {
2299 self.print_comment(cmnt)?;
2300 self.cur_cmnt_and_lit.cur_cmnt += 1;
2301 }
2302 }
2303 _ => (),
2304 }
2305 Ok(())
2306 }
2307
2308 pub fn print_remaining_comments(&mut self) -> io::Result<()> {
2309 // If there aren't any remaining comments, then we need to manually
2310 // make sure there is a line break at the end.
2311 if self.next_comment().is_none() {
2312 hardbreak(&mut self.s)?;
2313 }
2314 loop {
2315 match self.next_comment() {
2316 Some(ref cmnt) => {
2317 self.print_comment(cmnt)?;
2318 self.cur_cmnt_and_lit.cur_cmnt += 1;
2319 }
2320 _ => break,
2321 }
2322 }
2323 Ok(())
2324 }
2325
2326 pub fn print_opt_abi_and_extern_if_nondefault(&mut self,
2327 opt_abi: Option<Abi>)
2328 -> io::Result<()> {
2329 match opt_abi {
2330 Some(Abi::Rust) => Ok(()),
2331 Some(abi) => {
2332 self.word_nbsp("extern")?;
2333 self.word_nbsp(&abi.to_string())
2334 }
2335 None => Ok(()),
2336 }
2337 }
2338
2339 pub fn print_extern_opt_abi(&mut self, opt_abi: Option<Abi>) -> io::Result<()> {
2340 match opt_abi {
2341 Some(abi) => {
2342 self.word_nbsp("extern")?;
2343 self.word_nbsp(&abi.to_string())
2344 }
2345 None => Ok(()),
2346 }
2347 }
2348
2349 pub fn print_fn_header_info(&mut self,
2350 unsafety: hir::Unsafety,
2351 constness: hir::Constness,
2352 abi: Abi,
2353 vis: &hir::Visibility)
2354 -> io::Result<()> {
2355 word(&mut self.s, &visibility_qualified(vis, ""))?;
2356 self.print_unsafety(unsafety)?;
2357
2358 match constness {
2359 hir::Constness::NotConst => {}
2360 hir::Constness::Const => self.word_nbsp("const")?,
2361 }
2362
2363 if abi != Abi::Rust {
2364 self.word_nbsp("extern")?;
2365 self.word_nbsp(&abi.to_string())?;
2366 }
2367
2368 word(&mut self.s, "fn")
2369 }
2370
2371 pub fn print_unsafety(&mut self, s: hir::Unsafety) -> io::Result<()> {
2372 match s {
2373 hir::Unsafety::Normal => Ok(()),
2374 hir::Unsafety::Unsafe => self.word_nbsp("unsafe"),
2375 }
2376 }
2377 }
2378
2379 // Dup'ed from parse::classify, but adapted for the HIR.
2380 /// Does this expression require a semicolon to be treated
2381 /// as a statement? The negation of this: 'can this expression
2382 /// be used as a statement without a semicolon' -- is used
2383 /// as an early-bail-out in the parser so that, for instance,
2384 /// if true {...} else {...}
2385 /// |x| 5
2386 /// isn't parsed as (if true {...} else {...} | x) | 5
2387 fn expr_requires_semi_to_be_stmt(e: &hir::Expr) -> bool {
2388 match e.node {
2389 hir::ExprIf(..) |
2390 hir::ExprMatch(..) |
2391 hir::ExprBlock(_) |
2392 hir::ExprWhile(..) |
2393 hir::ExprLoop(..) => false,
2394 _ => true,
2395 }
2396 }
2397
2398 /// this statement requires a semicolon after it.
2399 /// note that in one case (stmt_semi), we've already
2400 /// seen the semicolon, and thus don't need another.
2401 fn stmt_ends_with_semi(stmt: &hir::Stmt_) -> bool {
2402 match *stmt {
2403 hir::StmtDecl(ref d, _) => {
2404 match d.node {
2405 hir::DeclLocal(_) => true,
2406 hir::DeclItem(_) => false,
2407 }
2408 }
2409 hir::StmtExpr(ref e, _) => {
2410 expr_requires_semi_to_be_stmt(&e)
2411 }
2412 hir::StmtSemi(..) => {
2413 false
2414 }
2415 }
2416 }