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.
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.
11 use rustc_target::spec::abi::{self, Abi};
12 use ast::{self, BlockCheckMode, PatKind, RangeEnd, RangeSyntax};
13 use ast::{SelfKind, GenericBound, TraitBoundModifier};
14 use ast::{Attribute, MacDelimiter, GenericArg};
15 use util::parser::{self, AssocOp, Fixity};
17 use source_map::{self, SourceMap, Spanned};
18 use syntax_pos::{self, BytePos};
19 use syntax_pos::hygiene::{Mark, SyntaxContext};
20 use parse::token::{self, BinOpToken, Token};
21 use parse::lexer::comments;
22 use parse::{self, ParseSess};
23 use print::pp::{self, Breaks};
24 use print::pp::Breaks::{Consistent, Inconsistent};
28 use syntax_pos::{DUMMY_SP, FileName};
29 use tokenstream::{self, TokenStream, TokenTree};
32 use std::io::{self, Write, Read};
33 use std::iter::Peekable;
36 pub enum AnnNode<'a> {
37 Ident(&'a ast::Ident),
39 Block(&'a ast::Block),
47 fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
48 fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) }
51 #[derive(Copy, Clone)]
54 impl PpAnn for NoAnn {}
56 pub struct State<'a> {
57 pub s: pp::Printer<'a>,
58 cm: Option<&'a SourceMap>,
59 comments: Option<Vec<comments::Comment> >,
60 literals: Peekable<vec::IntoIter<comments::Literal>>,
62 boxes: Vec<pp::Breaks>,
63 ann: &'a (dyn PpAnn+'a),
67 fn rust_printer<'a>(writer: Box<dyn Write+'a>, ann: &'a dyn PpAnn) -> State<'a> {
69 s: pp::mk_printer(writer, DEFAULT_COLUMNS),
72 literals: vec![].into_iter().peekable(),
80 pub const INDENT_UNIT: usize = 4;
82 pub const DEFAULT_COLUMNS: usize = 78;
84 /// Requires you to pass an input filename and reader so that
85 /// it can scan the input text for comments and literals to
87 pub fn print_crate<'a>(cm: &'a SourceMap,
92 out: Box<dyn Write+'a>,
94 is_expanded: bool) -> io::Result<()> {
95 let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded);
97 if is_expanded && std_inject::injected_crate_name().is_some() {
98 // We need to print `#![no_std]` (and its feature gate) so that
99 // compiling pretty-printed source won't inject libstd again.
100 // However we don't want these attributes in the AST because
101 // of the feature gate, so we fake them up here.
103 // #![feature(prelude_import)]
104 let pi_nested = attr::mk_nested_word_item(ast::Ident::from_str("prelude_import"));
105 let list = attr::mk_list_item(DUMMY_SP, ast::Ident::from_str("feature"), vec![pi_nested]);
106 let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), list);
107 s.print_attribute(&fake_attr)?;
110 let no_std_meta = attr::mk_word_item(ast::Ident::from_str("no_std"));
111 let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), no_std_meta);
112 s.print_attribute(&fake_attr)?;
115 s.print_mod(&krate.module, &krate.attrs)?;
116 s.print_remaining_comments()?;
121 pub fn new_from_input(cm: &'a SourceMap,
124 input: &mut dyn Read,
125 out: Box<dyn Write+'a>,
127 is_expanded: bool) -> State<'a> {
128 let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input);
135 // If the code is post expansion, don't use the table of
136 // literals, since it doesn't correspond with the literals
137 // in the AST anymore.
138 if is_expanded { None } else { Some(lits) },
143 pub fn new(cm: &'a SourceMap,
144 out: Box<dyn Write+'a>,
146 comments: Option<Vec<comments::Comment>>,
147 literals: Option<Vec<comments::Literal>>,
148 is_expanded: bool) -> State<'a> {
150 s: pp::mk_printer(out, DEFAULT_COLUMNS),
153 literals: literals.unwrap_or_default().into_iter().peekable(),
157 is_expanded: is_expanded
162 pub fn to_string<F>(f: F) -> String where
163 F: FnOnce(&mut State) -> io::Result<()>,
165 let mut wr = Vec::new();
168 let mut printer = rust_printer(Box::new(&mut wr), &ann);
169 f(&mut printer).unwrap();
170 printer.s.eof().unwrap();
172 String::from_utf8(wr).unwrap()
175 fn binop_to_string(op: BinOpToken) -> &'static str {
181 token::Percent => "%",
190 pub fn token_to_string(tok: &Token) -> String {
192 token::Eq => "=".to_string(),
193 token::Lt => "<".to_string(),
194 token::Le => "<=".to_string(),
195 token::EqEq => "==".to_string(),
196 token::Ne => "!=".to_string(),
197 token::Ge => ">=".to_string(),
198 token::Gt => ">".to_string(),
199 token::Not => "!".to_string(),
200 token::Tilde => "~".to_string(),
201 token::OrOr => "||".to_string(),
202 token::AndAnd => "&&".to_string(),
203 token::BinOp(op) => binop_to_string(op).to_string(),
204 token::BinOpEq(op) => format!("{}=", binop_to_string(op)),
206 /* Structural symbols */
207 token::At => "@".to_string(),
208 token::Dot => ".".to_string(),
209 token::DotDot => "..".to_string(),
210 token::DotDotDot => "...".to_string(),
211 token::DotDotEq => "..=".to_string(),
212 token::DotEq => ".=".to_string(),
213 token::Comma => ",".to_string(),
214 token::Semi => ";".to_string(),
215 token::Colon => ":".to_string(),
216 token::ModSep => "::".to_string(),
217 token::RArrow => "->".to_string(),
218 token::LArrow => "<-".to_string(),
219 token::FatArrow => "=>".to_string(),
220 token::OpenDelim(token::Paren) => "(".to_string(),
221 token::CloseDelim(token::Paren) => ")".to_string(),
222 token::OpenDelim(token::Bracket) => "[".to_string(),
223 token::CloseDelim(token::Bracket) => "]".to_string(),
224 token::OpenDelim(token::Brace) => "{".to_string(),
225 token::CloseDelim(token::Brace) => "}".to_string(),
226 token::OpenDelim(token::NoDelim) |
227 token::CloseDelim(token::NoDelim) => " ".to_string(),
228 token::Pound => "#".to_string(),
229 token::Dollar => "$".to_string(),
230 token::Question => "?".to_string(),
231 token::SingleQuote => "'".to_string(),
234 token::Literal(lit, suf) => {
235 let mut out = match lit {
236 token::Byte(b) => format!("b'{}'", b),
237 token::Char(c) => format!("'{}'", c),
239 token::Integer(c) => c.to_string(),
240 token::Str_(s) => format!("\"{}\"", s),
241 token::StrRaw(s, n) => format!("r{delim}\"{string}\"{delim}",
242 delim="#".repeat(n as usize),
244 token::ByteStr(v) => format!("b\"{}\"", v),
245 token::ByteStrRaw(s, n) => format!("br{delim}\"{string}\"{delim}",
246 delim="#".repeat(n as usize),
250 if let Some(s) = suf {
251 out.push_str(&s.as_str())
257 /* Name components */
258 token::Ident(s, false) => s.to_string(),
259 token::Ident(s, true) => format!("r#{}", s),
260 token::Lifetime(s) => s.to_string(),
263 token::DocComment(s) => s.to_string(),
264 token::Eof => "<eof>".to_string(),
265 token::Whitespace => " ".to_string(),
266 token::Comment => "/* */".to_string(),
267 token::Shebang(s) => format!("/* shebang: {}*/", s),
269 token::Interpolated(ref nt) => match nt.0 {
270 token::NtExpr(ref e) => expr_to_string(e),
271 token::NtMeta(ref e) => meta_item_to_string(e),
272 token::NtTy(ref e) => ty_to_string(e),
273 token::NtPath(ref e) => path_to_string(e),
274 token::NtItem(ref e) => item_to_string(e),
275 token::NtBlock(ref e) => block_to_string(e),
276 token::NtStmt(ref e) => stmt_to_string(e),
277 token::NtPat(ref e) => pat_to_string(e),
278 token::NtIdent(e, false) => ident_to_string(e),
279 token::NtIdent(e, true) => format!("r#{}", ident_to_string(e)),
280 token::NtLifetime(e) => ident_to_string(e),
281 token::NtLiteral(ref e) => expr_to_string(e),
282 token::NtTT(ref tree) => tt_to_string(tree.clone()),
283 token::NtArm(ref e) => arm_to_string(e),
284 token::NtImplItem(ref e) => impl_item_to_string(e),
285 token::NtTraitItem(ref e) => trait_item_to_string(e),
286 token::NtGenerics(ref e) => generic_params_to_string(&e.params),
287 token::NtWhereClause(ref e) => where_clause_to_string(e),
288 token::NtArg(ref e) => arg_to_string(e),
289 token::NtVis(ref e) => vis_to_string(e),
290 token::NtForeignItem(ref e) => foreign_item_to_string(e),
295 pub fn ty_to_string(ty: &ast::Ty) -> String {
296 to_string(|s| s.print_type(ty))
299 pub fn bounds_to_string(bounds: &[ast::GenericBound]) -> String {
300 to_string(|s| s.print_type_bounds("", bounds))
303 pub fn pat_to_string(pat: &ast::Pat) -> String {
304 to_string(|s| s.print_pat(pat))
307 pub fn arm_to_string(arm: &ast::Arm) -> String {
308 to_string(|s| s.print_arm(arm))
311 pub fn expr_to_string(e: &ast::Expr) -> String {
312 to_string(|s| s.print_expr(e))
315 pub fn lifetime_to_string(lt: &ast::Lifetime) -> String {
316 to_string(|s| s.print_lifetime(*lt))
319 pub fn tt_to_string(tt: tokenstream::TokenTree) -> String {
320 to_string(|s| s.print_tt(tt))
323 pub fn tts_to_string(tts: &[tokenstream::TokenTree]) -> String {
324 to_string(|s| s.print_tts(tts.iter().cloned().collect()))
327 pub fn tokens_to_string(tokens: TokenStream) -> String {
328 to_string(|s| s.print_tts(tokens))
331 pub fn stmt_to_string(stmt: &ast::Stmt) -> String {
332 to_string(|s| s.print_stmt(stmt))
335 pub fn attr_to_string(attr: &ast::Attribute) -> String {
336 to_string(|s| s.print_attribute(attr))
339 pub fn item_to_string(i: &ast::Item) -> String {
340 to_string(|s| s.print_item(i))
343 pub fn impl_item_to_string(i: &ast::ImplItem) -> String {
344 to_string(|s| s.print_impl_item(i))
347 pub fn trait_item_to_string(i: &ast::TraitItem) -> String {
348 to_string(|s| s.print_trait_item(i))
351 pub fn generic_params_to_string(generic_params: &[ast::GenericParam]) -> String {
352 to_string(|s| s.print_generic_params(generic_params))
355 pub fn where_clause_to_string(i: &ast::WhereClause) -> String {
356 to_string(|s| s.print_where_clause(i))
359 pub fn fn_block_to_string(p: &ast::FnDecl) -> String {
360 to_string(|s| s.print_fn_block_args(p))
363 pub fn path_to_string(p: &ast::Path) -> String {
364 to_string(|s| s.print_path(p, false, 0))
367 pub fn path_segment_to_string(p: &ast::PathSegment) -> String {
368 to_string(|s| s.print_path_segment(p, false))
371 pub fn ident_to_string(id: ast::Ident) -> String {
372 to_string(|s| s.print_ident(id))
375 pub fn vis_to_string(v: &ast::Visibility) -> String {
376 to_string(|s| s.print_visibility(v))
379 pub fn fun_to_string(decl: &ast::FnDecl,
380 header: ast::FnHeader,
382 generics: &ast::Generics)
386 s.print_fn(decl, header, Some(name),
387 generics, &source_map::dummy_spanned(ast::VisibilityKind::Inherited))?;
388 s.end()?; // Close the head box
389 s.end() // Close the outer box
393 pub fn block_to_string(blk: &ast::Block) -> String {
395 // containing cbox, will be closed by print-block at }
396 s.cbox(INDENT_UNIT)?;
397 // head-ibox, will be closed by print-block after {
403 pub fn meta_list_item_to_string(li: &ast::NestedMetaItem) -> String {
404 to_string(|s| s.print_meta_list_item(li))
407 pub fn meta_item_to_string(mi: &ast::MetaItem) -> String {
408 to_string(|s| s.print_meta_item(mi))
411 pub fn attribute_to_string(attr: &ast::Attribute) -> String {
412 to_string(|s| s.print_attribute(attr))
415 pub fn lit_to_string(l: &ast::Lit) -> String {
416 to_string(|s| s.print_literal(l))
419 pub fn variant_to_string(var: &ast::Variant) -> String {
420 to_string(|s| s.print_variant(var))
423 pub fn arg_to_string(arg: &ast::Arg) -> String {
424 to_string(|s| s.print_arg(arg, false))
427 pub fn mac_to_string(arg: &ast::Mac) -> String {
428 to_string(|s| s.print_mac(arg))
431 pub fn foreign_item_to_string(arg: &ast::ForeignItem) -> String {
432 to_string(|s| s.print_foreign_item(arg))
435 pub fn visibility_qualified(vis: &ast::Visibility, s: &str) -> String {
436 format!("{}{}", to_string(|s| s.print_visibility(vis)), s)
439 pub trait PrintState<'a> {
440 fn writer(&mut self) -> &mut pp::Printer<'a>;
441 fn boxes(&mut self) -> &mut Vec<pp::Breaks>;
442 fn comments(&mut self) -> &mut Option<Vec<comments::Comment>>;
443 fn cur_cmnt(&mut self) -> &mut usize;
444 fn cur_lit(&mut self) -> Option<&comments::Literal>;
445 fn bump_lit(&mut self) -> Option<comments::Literal>;
447 fn word_space(&mut self, w: &str) -> io::Result<()> {
448 self.writer().word(w)?;
449 self.writer().space()
452 fn popen(&mut self) -> io::Result<()> { self.writer().word("(") }
454 fn pclose(&mut self) -> io::Result<()> { self.writer().word(")") }
456 fn is_begin(&mut self) -> bool {
457 match self.writer().last_token() {
458 pp::Token::Begin(_) => true,
463 fn is_end(&mut self) -> bool {
464 match self.writer().last_token() {
465 pp::Token::End => true,
470 // is this the beginning of a line?
471 fn is_bol(&mut self) -> bool {
472 self.writer().last_token().is_eof() || self.writer().last_token().is_hardbreak_tok()
475 fn hardbreak_if_not_bol(&mut self) -> io::Result<()> {
477 self.writer().hardbreak()?
483 fn rbox(&mut self, u: usize, b: pp::Breaks) -> io::Result<()> {
484 self.boxes().push(b);
485 self.writer().rbox(u, b)
488 fn ibox(&mut self, u: usize) -> io::Result<()> {
489 self.boxes().push(pp::Breaks::Inconsistent);
490 self.writer().ibox(u)
493 fn end(&mut self) -> io::Result<()> {
494 self.boxes().pop().unwrap();
498 fn commasep<T, F>(&mut self, b: Breaks, elts: &[T], mut op: F) -> io::Result<()>
499 where F: FnMut(&mut Self, &T) -> io::Result<()>,
502 let mut first = true;
504 if first { first = false; } else { self.word_space(",")?; }
510 fn next_lit(&mut self, pos: BytePos) -> Option<comments::Literal> {
511 while let Some(ltrl) = self.cur_lit().cloned() {
512 if ltrl.pos > pos { break; }
514 // we don't need the value here since we're forced to clone cur_lit
515 // due to lack of NLL.
525 fn maybe_print_comment(&mut self, pos: BytePos) -> io::Result<()> {
526 while let Some(ref cmnt) = self.next_comment() {
528 self.print_comment(cmnt)?;
536 fn print_comment(&mut self,
537 cmnt: &comments::Comment) -> io::Result<()> {
538 let r = match cmnt.style {
540 assert_eq!(cmnt.lines.len(), 1);
541 self.writer().zerobreak()?;
542 self.writer().word(&cmnt.lines[0])?;
543 self.writer().zerobreak()
545 comments::Isolated => {
546 self.hardbreak_if_not_bol()?;
547 for line in &cmnt.lines {
548 // Don't print empty lines because they will end up as trailing
550 if !line.is_empty() {
551 self.writer().word(&line[..])?;
553 self.writer().hardbreak()?;
557 comments::Trailing => {
559 self.writer().word(" ")?;
561 if cmnt.lines.len() == 1 {
562 self.writer().word(&cmnt.lines[0])?;
563 self.writer().hardbreak()
566 for line in &cmnt.lines {
567 if !line.is_empty() {
568 self.writer().word(&line[..])?;
570 self.writer().hardbreak()?;
575 comments::BlankLine => {
576 // We need to do at least one, possibly two hardbreaks.
577 let is_semi = match self.writer().last_token() {
578 pp::Token::String(s, _) => ";" == s,
581 if is_semi || self.is_begin() || self.is_end() {
582 self.writer().hardbreak()?;
584 self.writer().hardbreak()
589 *self.cur_cmnt() = *self.cur_cmnt() + 1;
596 fn next_comment(&mut self) -> Option<comments::Comment> {
597 let cur_cmnt = *self.cur_cmnt();
598 match *self.comments() {
600 if cur_cmnt < cmnts.len() {
601 Some(cmnts[cur_cmnt].clone())
610 fn print_literal(&mut self, lit: &ast::Lit) -> io::Result<()> {
611 self.maybe_print_comment(lit.span.lo())?;
612 if let Some(ltrl) = self.next_lit(lit.span.lo()) {
613 return self.writer().word(<rl.lit);
616 ast::LitKind::Str(st, style) => self.print_string(&st.as_str(), style),
617 ast::LitKind::Byte(byte) => {
618 let mut res = String::from("b'");
619 res.extend(ascii::escape_default(byte).map(|c| c as char));
621 self.writer().word(&res[..])
623 ast::LitKind::Char(ch) => {
624 let mut res = String::from("'");
625 res.extend(ch.escape_default());
627 self.writer().word(&res[..])
629 ast::LitKind::Int(i, t) => {
631 ast::LitIntType::Signed(st) => {
632 self.writer().word(&st.val_to_string(i as i128))
634 ast::LitIntType::Unsigned(ut) => {
635 self.writer().word(&ut.val_to_string(i))
637 ast::LitIntType::Unsuffixed => {
638 self.writer().word(&i.to_string())
642 ast::LitKind::Float(ref f, t) => {
643 self.writer().word(&format!("{}{}", &f, t.ty_to_string()))
645 ast::LitKind::FloatUnsuffixed(ref f) => self.writer().word(&f.as_str()),
646 ast::LitKind::Bool(val) => {
647 if val { self.writer().word("true") } else { self.writer().word("false") }
649 ast::LitKind::ByteStr(ref v) => {
650 let mut escaped: String = String::new();
651 for &ch in v.iter() {
652 escaped.extend(ascii::escape_default(ch)
653 .map(|c| c as char));
655 self.writer().word(&format!("b\"{}\"", escaped))
660 fn print_string(&mut self, st: &str,
661 style: ast::StrStyle) -> io::Result<()> {
662 let st = match style {
663 ast::StrStyle::Cooked => {
664 (format!("\"{}\"", st.escape_debug()))
666 ast::StrStyle::Raw(n) => {
667 (format!("r{delim}\"{string}\"{delim}",
668 delim="#".repeat(n as usize),
672 self.writer().word(&st[..])
675 fn print_inner_attributes(&mut self,
676 attrs: &[ast::Attribute]) -> io::Result<()> {
677 self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, true)
680 fn print_inner_attributes_no_trailing_hardbreak(&mut self,
681 attrs: &[ast::Attribute])
683 self.print_either_attributes(attrs, ast::AttrStyle::Inner, false, false)
686 fn print_outer_attributes(&mut self,
687 attrs: &[ast::Attribute]) -> io::Result<()> {
688 self.print_either_attributes(attrs, ast::AttrStyle::Outer, false, true)
691 fn print_inner_attributes_inline(&mut self,
692 attrs: &[ast::Attribute]) -> io::Result<()> {
693 self.print_either_attributes(attrs, ast::AttrStyle::Inner, true, true)
696 fn print_outer_attributes_inline(&mut self,
697 attrs: &[ast::Attribute]) -> io::Result<()> {
698 self.print_either_attributes(attrs, ast::AttrStyle::Outer, true, true)
701 fn print_either_attributes(&mut self,
702 attrs: &[ast::Attribute],
703 kind: ast::AttrStyle,
705 trailing_hardbreak: bool) -> io::Result<()> {
708 if attr.style == kind {
709 self.print_attribute_inline(attr, is_inline)?;
716 if count > 0 && trailing_hardbreak && !is_inline {
717 self.hardbreak_if_not_bol()?;
722 fn print_attribute_path(&mut self, path: &ast::Path) -> io::Result<()> {
723 for (i, segment) in path.segments.iter().enumerate() {
725 self.writer().word("::")?
727 if segment.ident.name != keywords::CrateRoot.name() &&
728 segment.ident.name != keywords::DollarCrate.name()
730 self.writer().word(&segment.ident.as_str())?;
731 } else if segment.ident.name == keywords::DollarCrate.name() {
732 self.print_dollar_crate(segment.ident.span.ctxt())?;
738 fn print_attribute(&mut self, attr: &ast::Attribute) -> io::Result<()> {
739 self.print_attribute_inline(attr, false)
742 fn print_attribute_inline(&mut self, attr: &ast::Attribute,
743 is_inline: bool) -> io::Result<()> {
745 self.hardbreak_if_not_bol()?;
747 self.maybe_print_comment(attr.span.lo())?;
748 if attr.is_sugared_doc {
749 self.writer().word(&attr.value_str().unwrap().as_str())?;
750 self.writer().hardbreak()
753 ast::AttrStyle::Inner => self.writer().word("#![")?,
754 ast::AttrStyle::Outer => self.writer().word("#[")?,
756 if let Some(mi) = attr.meta() {
757 self.print_meta_item(&mi)?
759 self.print_attribute_path(&attr.path)?;
760 self.writer().space()?;
761 self.print_tts(attr.tokens.clone())?;
763 self.writer().word("]")
767 fn print_meta_list_item(&mut self, item: &ast::NestedMetaItem) -> io::Result<()> {
769 ast::NestedMetaItemKind::MetaItem(ref mi) => {
770 self.print_meta_item(mi)
772 ast::NestedMetaItemKind::Literal(ref lit) => {
773 self.print_literal(lit)
778 fn print_meta_item(&mut self, item: &ast::MetaItem) -> io::Result<()> {
779 self.ibox(INDENT_UNIT)?;
781 ast::MetaItemKind::Word => self.print_attribute_path(&item.ident)?,
782 ast::MetaItemKind::NameValue(ref value) => {
783 self.print_attribute_path(&item.ident)?;
784 self.writer().space()?;
785 self.word_space("=")?;
786 self.print_literal(value)?;
788 ast::MetaItemKind::List(ref items) => {
789 self.print_attribute_path(&item.ident)?;
791 self.commasep(Consistent,
793 |s, i| s.print_meta_list_item(i))?;
800 /// This doesn't deserve to be called "pretty" printing, but it should be
801 /// meaning-preserving. A quick hack that might help would be to look at the
802 /// spans embedded in the TTs to decide where to put spaces and newlines.
803 /// But it'd be better to parse these according to the grammar of the
804 /// appropriate macro, transcribe back into the grammar we just parsed from,
805 /// and then pretty-print the resulting AST nodes (so, e.g., we print
806 /// expression arguments as expressions). It can be done! I think.
807 fn print_tt(&mut self, tt: tokenstream::TokenTree) -> io::Result<()> {
809 TokenTree::Token(_, ref tk) => {
810 self.writer().word(&token_to_string(tk))?;
812 parse::token::DocComment(..) => {
813 self.writer().hardbreak()
818 TokenTree::Delimited(_, ref delimed) => {
819 self.writer().word(&token_to_string(&delimed.open_token()))?;
820 self.writer().space()?;
821 self.print_tts(delimed.stream())?;
822 self.writer().space()?;
823 self.writer().word(&token_to_string(&delimed.close_token()))
828 fn print_tts(&mut self, tts: tokenstream::TokenStream) -> io::Result<()> {
830 for (i, tt) in tts.into_trees().enumerate() {
832 self.writer().space()?;
839 fn space_if_not_bol(&mut self) -> io::Result<()> {
840 if !self.is_bol() { self.writer().space()?; }
844 fn nbsp(&mut self) -> io::Result<()> { self.writer().word(" ") }
846 fn print_dollar_crate(&mut self, mut ctxt: SyntaxContext) -> io::Result<()> {
847 if let Some(mark) = ctxt.adjust(Mark::root()) {
848 // Make a best effort to print something that complies
849 if mark.is_builtin() {
850 if let Some(name) = std_inject::injected_crate_name() {
851 self.writer().word("::")?;
852 self.writer().word(name)?;
860 impl<'a> PrintState<'a> for State<'a> {
861 fn writer(&mut self) -> &mut pp::Printer<'a> {
865 fn boxes(&mut self) -> &mut Vec<pp::Breaks> {
869 fn comments(&mut self) -> &mut Option<Vec<comments::Comment>> {
873 fn cur_cmnt(&mut self) -> &mut usize {
877 fn cur_lit(&mut self) -> Option<&comments::Literal> {
881 fn bump_lit(&mut self) -> Option<comments::Literal> {
887 pub fn cbox(&mut self, u: usize) -> io::Result<()> {
888 self.boxes.push(pp::Breaks::Consistent);
892 pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> {
897 pub fn head(&mut self, w: &str) -> io::Result<()> {
898 // outer-box is consistent
899 self.cbox(INDENT_UNIT)?;
900 // head-box is inconsistent
901 self.ibox(w.len() + 1)?;
902 // keyword that starts the head
909 pub fn bopen(&mut self) -> io::Result<()> {
911 self.end() // close the head-box
914 pub fn bclose_(&mut self, span: syntax_pos::Span,
915 indented: usize) -> io::Result<()> {
916 self.bclose_maybe_open(span, indented, true)
918 pub fn bclose_maybe_open(&mut self, span: syntax_pos::Span,
919 indented: usize, close_box: bool) -> io::Result<()> {
920 self.maybe_print_comment(span.hi())?;
921 self.break_offset_if_not_bol(1, -(indented as isize))?;
924 self.end()?; // close the outer-box
928 pub fn bclose(&mut self, span: syntax_pos::Span) -> io::Result<()> {
929 self.bclose_(span, INDENT_UNIT)
932 pub fn in_cbox(&self) -> bool {
933 match self.boxes.last() {
934 Some(&last_box) => last_box == pp::Breaks::Consistent,
939 pub fn break_offset_if_not_bol(&mut self, n: usize,
940 off: isize) -> io::Result<()> {
942 self.s.break_offset(n, off)
944 if off != 0 && self.s.last_token().is_hardbreak_tok() {
945 // We do something pretty sketchy here: tuck the nonzero
946 // offset-adjustment we were going to deposit along with the
947 // break into the previous hardbreak.
948 self.s.replace_last_token(pp::Printer::hardbreak_tok_offset(off));
954 // Synthesizes a comment that was not textually present in the original source
956 pub fn synth_comment(&mut self, text: String) -> io::Result<()> {
959 self.s.word(&text[..])?;
966 pub fn commasep_cmnt<T, F, G>(&mut self,
970 mut get_span: G) -> io::Result<()> where
971 F: FnMut(&mut State, &T) -> io::Result<()>,
972 G: FnMut(&T) -> syntax_pos::Span,
975 let len = elts.len();
978 self.maybe_print_comment(get_span(elt).hi())?;
983 self.maybe_print_trailing_comment(get_span(elt),
984 Some(get_span(&elts[i]).hi()))?;
985 self.space_if_not_bol()?;
991 pub fn commasep_exprs(&mut self, b: Breaks,
992 exprs: &[P<ast::Expr>]) -> io::Result<()> {
993 self.commasep_cmnt(b, exprs, |s, e| s.print_expr(e), |e| e.span)
996 pub fn print_mod(&mut self, _mod: &ast::Mod,
997 attrs: &[ast::Attribute]) -> io::Result<()> {
998 self.print_inner_attributes(attrs)?;
999 for item in &_mod.items {
1000 self.print_item(item)?;
1005 pub fn print_foreign_mod(&mut self, nmod: &ast::ForeignMod,
1006 attrs: &[ast::Attribute]) -> io::Result<()> {
1007 self.print_inner_attributes(attrs)?;
1008 for item in &nmod.items {
1009 self.print_foreign_item(item)?;
1014 pub fn print_opt_lifetime(&mut self, lifetime: &Option<ast::Lifetime>) -> io::Result<()> {
1015 if let Some(lt) = *lifetime {
1016 self.print_lifetime(lt)?;
1022 pub fn print_generic_arg(&mut self, generic_arg: &GenericArg) -> io::Result<()> {
1024 GenericArg::Lifetime(lt) => self.print_lifetime(*lt),
1025 GenericArg::Type(ty) => self.print_type(ty),
1029 pub fn print_type(&mut self, ty: &ast::Ty) -> io::Result<()> {
1030 self.maybe_print_comment(ty.span.lo())?;
1033 ast::TyKind::Slice(ref ty) => {
1035 self.print_type(ty)?;
1038 ast::TyKind::Ptr(ref mt) => {
1041 ast::Mutability::Mutable => self.word_nbsp("mut")?,
1042 ast::Mutability::Immutable => self.word_nbsp("const")?,
1044 self.print_type(&mt.ty)?;
1046 ast::TyKind::Rptr(ref lifetime, ref mt) => {
1048 self.print_opt_lifetime(lifetime)?;
1051 ast::TyKind::Never => {
1054 ast::TyKind::Tup(ref elts) => {
1056 self.commasep(Inconsistent, &elts[..],
1057 |s, ty| s.print_type(ty))?;
1058 if elts.len() == 1 {
1063 ast::TyKind::Paren(ref typ) => {
1065 self.print_type(typ)?;
1068 ast::TyKind::BareFn(ref f) => {
1069 self.print_ty_fn(f.abi,
1073 &f.generic_params)?;
1075 ast::TyKind::Path(None, ref path) => {
1076 self.print_path(path, false, 0)?;
1078 ast::TyKind::Path(Some(ref qself), ref path) => {
1079 self.print_qpath(path, qself, false)?
1081 ast::TyKind::TraitObject(ref bounds, syntax) => {
1082 let prefix = if syntax == ast::TraitObjectSyntax::Dyn { "dyn" } else { "" };
1083 self.print_type_bounds(prefix, &bounds[..])?;
1085 ast::TyKind::ImplTrait(_, ref bounds) => {
1086 self.print_type_bounds("impl", &bounds[..])?;
1088 ast::TyKind::Array(ref ty, ref length) => {
1090 self.print_type(ty)?;
1092 self.print_expr(&length.value)?;
1095 ast::TyKind::Typeof(ref e) => {
1096 self.s.word("typeof(")?;
1097 self.print_expr(&e.value)?;
1100 ast::TyKind::Infer => {
1103 ast::TyKind::Err => {
1106 ast::TyKind::ImplicitSelf => {
1107 self.s.word("Self")?;
1109 ast::TyKind::Mac(ref m) => {
1116 pub fn print_foreign_item(&mut self,
1117 item: &ast::ForeignItem) -> io::Result<()> {
1118 self.hardbreak_if_not_bol()?;
1119 self.maybe_print_comment(item.span.lo())?;
1120 self.print_outer_attributes(&item.attrs)?;
1122 ast::ForeignItemKind::Fn(ref decl, ref generics) => {
1124 self.print_fn(decl, ast::FnHeader::default(),
1126 generics, &item.vis)?;
1127 self.end()?; // end head-ibox
1129 self.end() // end the outer fn box
1131 ast::ForeignItemKind::Static(ref t, m) => {
1132 self.head(&visibility_qualified(&item.vis, "static"))?;
1134 self.word_space("mut")?;
1136 self.print_ident(item.ident)?;
1137 self.word_space(":")?;
1138 self.print_type(t)?;
1140 self.end()?; // end the head-ibox
1141 self.end() // end the outer cbox
1143 ast::ForeignItemKind::Ty => {
1144 self.head(&visibility_qualified(&item.vis, "type"))?;
1145 self.print_ident(item.ident)?;
1147 self.end()?; // end the head-ibox
1148 self.end() // end the outer cbox
1150 ast::ForeignItemKind::Macro(ref m) => {
1152 match m.node.delim {
1153 MacDelimiter::Brace => Ok(()),
1154 _ => self.s.word(";")
1160 fn print_associated_const(&mut self,
1163 default: Option<&ast::Expr>,
1164 vis: &ast::Visibility)
1167 self.s.word(&visibility_qualified(vis, ""))?;
1168 self.word_space("const")?;
1169 self.print_ident(ident)?;
1170 self.word_space(":")?;
1171 self.print_type(ty)?;
1172 if let Some(expr) = default {
1174 self.word_space("=")?;
1175 self.print_expr(expr)?;
1180 fn print_associated_type(&mut self,
1182 bounds: Option<&ast::GenericBounds>,
1183 ty: Option<&ast::Ty>)
1185 self.word_space("type")?;
1186 self.print_ident(ident)?;
1187 if let Some(bounds) = bounds {
1188 self.print_type_bounds(":", bounds)?;
1190 if let Some(ty) = ty {
1192 self.word_space("=")?;
1193 self.print_type(ty)?;
1198 /// Pretty-print an item
1199 pub fn print_item(&mut self, item: &ast::Item) -> io::Result<()> {
1200 self.hardbreak_if_not_bol()?;
1201 self.maybe_print_comment(item.span.lo())?;
1202 self.print_outer_attributes(&item.attrs)?;
1203 self.ann.pre(self, AnnNode::Item(item))?;
1205 ast::ItemKind::ExternCrate(orig_name) => {
1206 self.head(&visibility_qualified(&item.vis, "extern crate"))?;
1207 if let Some(orig_name) = orig_name {
1208 self.print_name(orig_name)?;
1213 self.print_ident(item.ident)?;
1215 self.end()?; // end inner head-block
1216 self.end()?; // end outer head-block
1218 ast::ItemKind::Use(ref tree) => {
1219 self.head(&visibility_qualified(&item.vis, "use"))?;
1220 self.print_use_tree(tree)?;
1222 self.end()?; // end inner head-block
1223 self.end()?; // end outer head-block
1225 ast::ItemKind::Static(ref ty, m, ref expr) => {
1226 self.head(&visibility_qualified(&item.vis, "static"))?;
1227 if m == ast::Mutability::Mutable {
1228 self.word_space("mut")?;
1230 self.print_ident(item.ident)?;
1231 self.word_space(":")?;
1232 self.print_type(ty)?;
1234 self.end()?; // end the head-ibox
1236 self.word_space("=")?;
1237 self.print_expr(expr)?;
1239 self.end()?; // end the outer cbox
1241 ast::ItemKind::Const(ref ty, ref expr) => {
1242 self.head(&visibility_qualified(&item.vis, "const"))?;
1243 self.print_ident(item.ident)?;
1244 self.word_space(":")?;
1245 self.print_type(ty)?;
1247 self.end()?; // end the head-ibox
1249 self.word_space("=")?;
1250 self.print_expr(expr)?;
1252 self.end()?; // end the outer cbox
1254 ast::ItemKind::Fn(ref decl, header, ref typarams, ref body) => {
1264 self.print_block_with_attrs(body, &item.attrs)?;
1266 ast::ItemKind::Mod(ref _mod) => {
1267 self.head(&visibility_qualified(&item.vis, "mod"))?;
1268 self.print_ident(item.ident)?;
1270 if _mod.inline || self.is_expanded {
1273 self.print_mod(_mod, &item.attrs)?;
1274 self.bclose(item.span)?;
1277 self.end()?; // end inner head-block
1278 self.end()?; // end outer head-block
1282 ast::ItemKind::ForeignMod(ref nmod) => {
1283 self.head("extern")?;
1284 self.word_nbsp(&nmod.abi.to_string())?;
1286 self.print_foreign_mod(nmod, &item.attrs)?;
1287 self.bclose(item.span)?;
1289 ast::ItemKind::GlobalAsm(ref ga) => {
1290 self.head(&visibility_qualified(&item.vis, "global_asm!"))?;
1291 self.s.word(&ga.asm.as_str())?;
1294 ast::ItemKind::Ty(ref ty, ref generics) => {
1295 self.head(&visibility_qualified(&item.vis, "type"))?;
1296 self.print_ident(item.ident)?;
1297 self.print_generic_params(&generics.params)?;
1298 self.end()?; // end the inner ibox
1300 self.print_where_clause(&generics.where_clause)?;
1302 self.word_space("=")?;
1303 self.print_type(ty)?;
1305 self.end()?; // end the outer ibox
1307 ast::ItemKind::Existential(ref bounds, ref generics) => {
1308 self.head(&visibility_qualified(&item.vis, "existential type"))?;
1309 self.print_ident(item.ident)?;
1310 self.print_generic_params(&generics.params)?;
1311 self.end()?; // end the inner ibox
1313 self.print_where_clause(&generics.where_clause)?;
1315 self.print_type_bounds(":", bounds)?;
1317 self.end()?; // end the outer ibox
1319 ast::ItemKind::Enum(ref enum_definition, ref params) => {
1320 self.print_enum_def(
1328 ast::ItemKind::Struct(ref struct_def, ref generics) => {
1329 self.head(&visibility_qualified(&item.vis, "struct"))?;
1330 self.print_struct(struct_def, generics, item.ident, item.span, true)?;
1332 ast::ItemKind::Union(ref struct_def, ref generics) => {
1333 self.head(&visibility_qualified(&item.vis, "union"))?;
1334 self.print_struct(struct_def, generics, item.ident, item.span, true)?;
1336 ast::ItemKind::Impl(unsafety,
1342 ref impl_items) => {
1344 self.print_visibility(&item.vis)?;
1345 self.print_defaultness(defaultness)?;
1346 self.print_unsafety(unsafety)?;
1347 self.word_nbsp("impl")?;
1349 if !generics.params.is_empty() {
1350 self.print_generic_params(&generics.params)?;
1354 if polarity == ast::ImplPolarity::Negative {
1358 if let Some(ref t) = *opt_trait {
1359 self.print_trait_ref(t)?;
1361 self.word_space("for")?;
1364 self.print_type(ty)?;
1365 self.print_where_clause(&generics.where_clause)?;
1369 self.print_inner_attributes(&item.attrs)?;
1370 for impl_item in impl_items {
1371 self.print_impl_item(impl_item)?;
1373 self.bclose(item.span)?;
1375 ast::ItemKind::Trait(is_auto, unsafety, ref generics, ref bounds, ref trait_items) => {
1377 self.print_visibility(&item.vis)?;
1378 self.print_unsafety(unsafety)?;
1379 self.print_is_auto(is_auto)?;
1380 self.word_nbsp("trait")?;
1381 self.print_ident(item.ident)?;
1382 self.print_generic_params(&generics.params)?;
1383 let mut real_bounds = Vec::with_capacity(bounds.len());
1384 for b in bounds.iter() {
1385 if let GenericBound::Trait(ref ptr, ast::TraitBoundModifier::Maybe) = *b {
1387 self.word_space("for ?")?;
1388 self.print_trait_ref(&ptr.trait_ref)?;
1390 real_bounds.push(b.clone());
1393 self.print_type_bounds(":", &real_bounds[..])?;
1394 self.print_where_clause(&generics.where_clause)?;
1397 for trait_item in trait_items {
1398 self.print_trait_item(trait_item)?;
1400 self.bclose(item.span)?;
1402 ast::ItemKind::TraitAlias(ref generics, ref bounds) => {
1404 self.print_visibility(&item.vis)?;
1405 self.word_nbsp("trait")?;
1406 self.print_ident(item.ident)?;
1407 self.print_generic_params(&generics.params)?;
1408 let mut real_bounds = Vec::with_capacity(bounds.len());
1409 // FIXME(durka) this seems to be some quite outdated syntax
1410 for b in bounds.iter() {
1411 if let GenericBound::Trait(ref ptr, ast::TraitBoundModifier::Maybe) = *b {
1413 self.word_space("for ?")?;
1414 self.print_trait_ref(&ptr.trait_ref)?;
1416 real_bounds.push(b.clone());
1420 self.print_type_bounds("=", &real_bounds[..])?;
1421 self.print_where_clause(&generics.where_clause)?;
1424 ast::ItemKind::Mac(ref mac) => {
1425 if item.ident.name == keywords::Invalid.name() {
1426 self.print_mac(mac)?;
1427 match mac.node.delim {
1428 MacDelimiter::Brace => {}
1429 _ => self.s.word(";")?,
1432 self.print_path(&mac.node.path, false, 0)?;
1434 self.print_ident(item.ident)?;
1435 self.cbox(INDENT_UNIT)?;
1437 self.print_tts(mac.node.stream())?;
1443 ast::ItemKind::MacroDef(ref tts) => {
1444 self.s.word("macro_rules! ")?;
1445 self.print_ident(item.ident)?;
1446 self.cbox(INDENT_UNIT)?;
1448 self.print_tts(tts.stream())?;
1454 self.ann.post(self, AnnNode::Item(item))
1457 fn print_trait_ref(&mut self, t: &ast::TraitRef) -> io::Result<()> {
1458 self.print_path(&t.path, false, 0)
1461 fn print_formal_generic_params(
1463 generic_params: &[ast::GenericParam]
1464 ) -> io::Result<()> {
1465 if !generic_params.is_empty() {
1466 self.s.word("for")?;
1467 self.print_generic_params(generic_params)?;
1473 fn print_poly_trait_ref(&mut self, t: &ast::PolyTraitRef) -> io::Result<()> {
1474 self.print_formal_generic_params(&t.bound_generic_params)?;
1475 self.print_trait_ref(&t.trait_ref)
1478 pub fn print_enum_def(&mut self, enum_definition: &ast::EnumDef,
1479 generics: &ast::Generics, ident: ast::Ident,
1480 span: syntax_pos::Span,
1481 visibility: &ast::Visibility) -> io::Result<()> {
1482 self.head(&visibility_qualified(visibility, "enum"))?;
1483 self.print_ident(ident)?;
1484 self.print_generic_params(&generics.params)?;
1485 self.print_where_clause(&generics.where_clause)?;
1487 self.print_variants(&enum_definition.variants, span)
1490 pub fn print_variants(&mut self,
1491 variants: &[ast::Variant],
1492 span: syntax_pos::Span) -> io::Result<()> {
1495 self.space_if_not_bol()?;
1496 self.maybe_print_comment(v.span.lo())?;
1497 self.print_outer_attributes(&v.node.attrs)?;
1498 self.ibox(INDENT_UNIT)?;
1499 self.print_variant(v)?;
1502 self.maybe_print_trailing_comment(v.span, None)?;
1507 pub fn print_visibility(&mut self, vis: &ast::Visibility) -> io::Result<()> {
1509 ast::VisibilityKind::Public => self.word_nbsp("pub"),
1510 ast::VisibilityKind::Crate(sugar) => match sugar {
1511 ast::CrateSugar::PubCrate => self.word_nbsp("pub(crate)"),
1512 ast::CrateSugar::JustCrate => self.word_nbsp("crate")
1514 ast::VisibilityKind::Restricted { ref path, .. } => {
1515 let path = to_string(|s| s.print_path(path, false, 0));
1516 if path == "self" || path == "super" {
1517 self.word_nbsp(&format!("pub({})", path))
1519 self.word_nbsp(&format!("pub(in {})", path))
1522 ast::VisibilityKind::Inherited => Ok(())
1526 pub fn print_defaultness(&mut self, defaultness: ast::Defaultness) -> io::Result<()> {
1527 if let ast::Defaultness::Default = defaultness {
1528 try!(self.word_nbsp("default"));
1533 pub fn print_struct(&mut self,
1534 struct_def: &ast::VariantData,
1535 generics: &ast::Generics,
1537 span: syntax_pos::Span,
1538 print_finalizer: bool) -> io::Result<()> {
1539 self.print_ident(ident)?;
1540 self.print_generic_params(&generics.params)?;
1541 if !struct_def.is_struct() {
1542 if struct_def.is_tuple() {
1545 Inconsistent, struct_def.fields(),
1547 s.maybe_print_comment(field.span.lo())?;
1548 s.print_outer_attributes(&field.attrs)?;
1549 s.print_visibility(&field.vis)?;
1550 s.print_type(&field.ty)
1555 self.print_where_clause(&generics.where_clause)?;
1556 if print_finalizer {
1560 self.end() // close the outer-box
1562 self.print_where_clause(&generics.where_clause)?;
1565 self.hardbreak_if_not_bol()?;
1567 for field in struct_def.fields() {
1568 self.hardbreak_if_not_bol()?;
1569 self.maybe_print_comment(field.span.lo())?;
1570 self.print_outer_attributes(&field.attrs)?;
1571 self.print_visibility(&field.vis)?;
1572 self.print_ident(field.ident.unwrap())?;
1573 self.word_nbsp(":")?;
1574 self.print_type(&field.ty)?;
1582 pub fn print_variant(&mut self, v: &ast::Variant) -> io::Result<()> {
1584 let generics = ast::Generics::default();
1585 self.print_struct(&v.node.data, &generics, v.node.ident, v.span, false)?;
1586 match v.node.disr_expr {
1589 self.word_space("=")?;
1590 self.print_expr(&d.value)
1596 pub fn print_method_sig(&mut self,
1598 generics: &ast::Generics,
1600 vis: &ast::Visibility)
1602 self.print_fn(&m.decl,
1609 pub fn print_trait_item(&mut self, ti: &ast::TraitItem)
1611 self.ann.pre(self, AnnNode::SubItem(ti.id))?;
1612 self.hardbreak_if_not_bol()?;
1613 self.maybe_print_comment(ti.span.lo())?;
1614 self.print_outer_attributes(&ti.attrs)?;
1616 ast::TraitItemKind::Const(ref ty, ref default) => {
1617 self.print_associated_const(
1620 default.as_ref().map(|expr| &**expr),
1621 &source_map::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
1624 ast::TraitItemKind::Method(ref sig, ref body) => {
1628 self.print_method_sig(
1632 &source_map::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
1634 if let Some(ref body) = *body {
1636 self.print_block_with_attrs(body, &ti.attrs)?;
1641 ast::TraitItemKind::Type(ref bounds, ref default) => {
1642 self.print_associated_type(ti.ident, Some(bounds),
1643 default.as_ref().map(|ty| &**ty))?;
1645 ast::TraitItemKind::Macro(ref mac) => {
1646 self.print_mac(mac)?;
1647 match mac.node.delim {
1648 MacDelimiter::Brace => {}
1649 _ => self.s.word(";")?,
1653 self.ann.post(self, AnnNode::SubItem(ti.id))
1656 pub fn print_impl_item(&mut self, ii: &ast::ImplItem) -> io::Result<()> {
1657 self.ann.pre(self, AnnNode::SubItem(ii.id))?;
1658 self.hardbreak_if_not_bol()?;
1659 self.maybe_print_comment(ii.span.lo())?;
1660 self.print_outer_attributes(&ii.attrs)?;
1661 self.print_defaultness(ii.defaultness)?;
1663 ast::ImplItemKind::Const(ref ty, ref expr) => {
1664 self.print_associated_const(ii.ident, ty, Some(expr), &ii.vis)?;
1666 ast::ImplItemKind::Method(ref sig, ref body) => {
1668 self.print_method_sig(ii.ident, &ii.generics, sig, &ii.vis)?;
1670 self.print_block_with_attrs(body, &ii.attrs)?;
1672 ast::ImplItemKind::Type(ref ty) => {
1673 self.print_associated_type(ii.ident, None, Some(ty))?;
1675 ast::ImplItemKind::Existential(ref bounds) => {
1676 self.word_space("existential")?;
1677 self.print_associated_type(ii.ident, Some(bounds), None)?;
1679 ast::ImplItemKind::Macro(ref mac) => {
1680 self.print_mac(mac)?;
1681 match mac.node.delim {
1682 MacDelimiter::Brace => {}
1683 _ => self.s.word(";")?,
1687 self.ann.post(self, AnnNode::SubItem(ii.id))
1690 pub fn print_stmt(&mut self, st: &ast::Stmt) -> io::Result<()> {
1691 self.maybe_print_comment(st.span.lo())?;
1693 ast::StmtKind::Local(ref loc) => {
1694 self.print_outer_attributes(&loc.attrs)?;
1695 self.space_if_not_bol()?;
1696 self.ibox(INDENT_UNIT)?;
1697 self.word_nbsp("let")?;
1699 self.ibox(INDENT_UNIT)?;
1700 self.print_local_decl(loc)?;
1702 if let Some(ref init) = loc.init {
1704 self.word_space("=")?;
1705 self.print_expr(init)?;
1710 ast::StmtKind::Item(ref item) => self.print_item(item)?,
1711 ast::StmtKind::Expr(ref expr) => {
1712 self.space_if_not_bol()?;
1713 self.print_expr_outer_attr_style(expr, false)?;
1714 if parse::classify::expr_requires_semi_to_be_stmt(expr) {
1718 ast::StmtKind::Semi(ref expr) => {
1719 self.space_if_not_bol()?;
1720 self.print_expr_outer_attr_style(expr, false)?;
1723 ast::StmtKind::Mac(ref mac) => {
1724 let (ref mac, style, ref attrs) = **mac;
1725 self.space_if_not_bol()?;
1726 self.print_outer_attributes(attrs)?;
1727 self.print_mac(mac)?;
1728 if style == ast::MacStmtStyle::Semicolon {
1733 self.maybe_print_trailing_comment(st.span, None)
1736 pub fn print_block(&mut self, blk: &ast::Block) -> io::Result<()> {
1737 self.print_block_with_attrs(blk, &[])
1740 pub fn print_block_unclosed(&mut self, blk: &ast::Block) -> io::Result<()> {
1741 self.print_block_unclosed_indent(blk, INDENT_UNIT)
1744 pub fn print_block_unclosed_with_attrs(&mut self, blk: &ast::Block,
1745 attrs: &[ast::Attribute])
1747 self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, false)
1750 pub fn print_block_unclosed_indent(&mut self, blk: &ast::Block,
1751 indented: usize) -> io::Result<()> {
1752 self.print_block_maybe_unclosed(blk, indented, &[], false)
1755 pub fn print_block_with_attrs(&mut self,
1757 attrs: &[ast::Attribute]) -> io::Result<()> {
1758 self.print_block_maybe_unclosed(blk, INDENT_UNIT, attrs, true)
1761 pub fn print_block_maybe_unclosed(&mut self,
1764 attrs: &[ast::Attribute],
1765 close_box: bool) -> io::Result<()> {
1767 BlockCheckMode::Unsafe(..) => self.word_space("unsafe")?,
1768 BlockCheckMode::Default => ()
1770 self.maybe_print_comment(blk.span.lo())?;
1771 self.ann.pre(self, AnnNode::Block(blk))?;
1774 self.print_inner_attributes(attrs)?;
1776 for (i, st) in blk.stmts.iter().enumerate() {
1778 ast::StmtKind::Expr(ref expr) if i == blk.stmts.len() - 1 => {
1779 self.maybe_print_comment(st.span.lo())?;
1780 self.space_if_not_bol()?;
1781 self.print_expr_outer_attr_style(expr, false)?;
1782 self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi()))?;
1784 _ => self.print_stmt(st)?,
1788 self.bclose_maybe_open(blk.span, indented, close_box)?;
1789 self.ann.post(self, AnnNode::Block(blk))
1792 fn print_else(&mut self, els: Option<&ast::Expr>) -> io::Result<()> {
1796 // "another else-if"
1797 ast::ExprKind::If(ref i, ref then, ref e) => {
1798 self.cbox(INDENT_UNIT - 1)?;
1800 self.s.word(" else if ")?;
1801 self.print_expr_as_cond(i)?;
1803 self.print_block(then)?;
1804 self.print_else(e.as_ref().map(|e| &**e))
1806 // "another else-if-let"
1807 ast::ExprKind::IfLet(ref pats, ref expr, ref then, ref e) => {
1808 self.cbox(INDENT_UNIT - 1)?;
1810 self.s.word(" else if let ")?;
1811 self.print_pats(pats)?;
1813 self.word_space("=")?;
1814 self.print_expr_as_cond(expr)?;
1816 self.print_block(then)?;
1817 self.print_else(e.as_ref().map(|e| &**e))
1820 ast::ExprKind::Block(ref b, _) => {
1821 self.cbox(INDENT_UNIT - 1)?;
1823 self.s.word(" else ")?;
1826 // BLEAH, constraints would be great here
1828 panic!("print_if saw if with weird alternative");
1836 pub fn print_if(&mut self, test: &ast::Expr, blk: &ast::Block,
1837 elseopt: Option<&ast::Expr>) -> io::Result<()> {
1839 self.print_expr_as_cond(test)?;
1841 self.print_block(blk)?;
1842 self.print_else(elseopt)
1845 pub fn print_if_let(&mut self, pats: &[P<ast::Pat>], expr: &ast::Expr, blk: &ast::Block,
1846 elseopt: Option<&ast::Expr>) -> io::Result<()> {
1847 self.head("if let")?;
1848 self.print_pats(pats)?;
1850 self.word_space("=")?;
1851 self.print_expr_as_cond(expr)?;
1853 self.print_block(blk)?;
1854 self.print_else(elseopt)
1857 pub fn print_mac(&mut self, m: &ast::Mac) -> io::Result<()> {
1858 self.print_path(&m.node.path, false, 0)?;
1860 match m.node.delim {
1861 MacDelimiter::Parenthesis => self.popen()?,
1862 MacDelimiter::Bracket => self.s.word("[")?,
1863 MacDelimiter::Brace => {
1868 self.print_tts(m.node.stream())?;
1869 match m.node.delim {
1870 MacDelimiter::Parenthesis => self.pclose(),
1871 MacDelimiter::Bracket => self.s.word("]"),
1872 MacDelimiter::Brace => self.bclose(m.span),
1877 fn print_call_post(&mut self, args: &[P<ast::Expr>]) -> io::Result<()> {
1879 self.commasep_exprs(Inconsistent, args)?;
1883 pub fn print_expr_maybe_paren(&mut self, expr: &ast::Expr, prec: i8) -> io::Result<()> {
1884 let needs_par = expr.precedence().order() < prec;
1888 self.print_expr(expr)?;
1895 /// Print an expr using syntax that's acceptable in a condition position, such as the `cond` in
1896 /// `if cond { ... }`.
1897 pub fn print_expr_as_cond(&mut self, expr: &ast::Expr) -> io::Result<()> {
1898 let needs_par = match expr.node {
1899 // These cases need parens due to the parse error observed in #26461: `if return {}`
1900 // parses as the erroneous construct `if (return {})`, not `if (return) {}`.
1901 ast::ExprKind::Closure(..) |
1902 ast::ExprKind::Ret(..) |
1903 ast::ExprKind::Break(..) => true,
1905 _ => parser::contains_exterior_struct_lit(expr),
1911 self.print_expr(expr)?;
1918 fn print_expr_vec(&mut self, exprs: &[P<ast::Expr>],
1919 attrs: &[Attribute]) -> io::Result<()> {
1920 self.ibox(INDENT_UNIT)?;
1922 self.print_inner_attributes_inline(attrs)?;
1923 self.commasep_exprs(Inconsistent, &exprs[..])?;
1928 fn print_expr_repeat(&mut self,
1929 element: &ast::Expr,
1930 count: &ast::AnonConst,
1931 attrs: &[Attribute]) -> io::Result<()> {
1932 self.ibox(INDENT_UNIT)?;
1934 self.print_inner_attributes_inline(attrs)?;
1935 self.print_expr(element)?;
1936 self.word_space(";")?;
1937 self.print_expr(&count.value)?;
1942 fn print_expr_struct(&mut self,
1944 fields: &[ast::Field],
1945 wth: &Option<P<ast::Expr>>,
1946 attrs: &[Attribute]) -> io::Result<()> {
1947 self.print_path(path, true, 0)?;
1949 self.print_inner_attributes_inline(attrs)?;
1954 s.ibox(INDENT_UNIT)?;
1955 if !field.is_shorthand {
1956 s.print_ident(field.ident)?;
1959 s.print_expr(&field.expr)?;
1965 self.ibox(INDENT_UNIT)?;
1966 if !fields.is_empty() {
1971 self.print_expr(expr)?;
1974 _ => if !fields.is_empty() {
1982 fn print_expr_tup(&mut self, exprs: &[P<ast::Expr>],
1983 attrs: &[Attribute]) -> io::Result<()> {
1985 self.print_inner_attributes_inline(attrs)?;
1986 self.commasep_exprs(Inconsistent, &exprs[..])?;
1987 if exprs.len() == 1 {
1993 fn print_expr_call(&mut self,
1995 args: &[P<ast::Expr>]) -> io::Result<()> {
1998 ast::ExprKind::Field(..) => parser::PREC_FORCE_PAREN,
1999 _ => parser::PREC_POSTFIX,
2002 self.print_expr_maybe_paren(func, prec)?;
2003 self.print_call_post(args)
2006 fn print_expr_method_call(&mut self,
2007 segment: &ast::PathSegment,
2008 args: &[P<ast::Expr>]) -> io::Result<()> {
2009 let base_args = &args[1..];
2010 self.print_expr_maybe_paren(&args[0], parser::PREC_POSTFIX)?;
2012 self.print_ident(segment.ident)?;
2013 if let Some(ref args) = segment.args {
2014 self.print_generic_args(args, true)?;
2016 self.print_call_post(base_args)
2019 fn print_expr_binary(&mut self,
2022 rhs: &ast::Expr) -> io::Result<()> {
2023 let assoc_op = AssocOp::from_ast_binop(op.node);
2024 let prec = assoc_op.precedence() as i8;
2025 let fixity = assoc_op.fixity();
2027 let (left_prec, right_prec) = match fixity {
2028 Fixity::Left => (prec, prec + 1),
2029 Fixity::Right => (prec + 1, prec),
2030 Fixity::None => (prec + 1, prec + 1),
2033 let left_prec = match (&lhs.node, op.node) {
2034 // These cases need parens: `x as i32 < y` has the parser thinking that `i32 < y` is
2035 // the beginning of a path type. It starts trying to parse `x as (i32 < y ...` instead
2036 // of `(x as i32) < ...`. We need to convince it _not_ to do that.
2037 (&ast::ExprKind::Cast { .. }, ast::BinOpKind::Lt) |
2038 (&ast::ExprKind::Cast { .. }, ast::BinOpKind::Shl) => parser::PREC_FORCE_PAREN,
2042 self.print_expr_maybe_paren(lhs, left_prec)?;
2044 self.word_space(op.node.to_string())?;
2045 self.print_expr_maybe_paren(rhs, right_prec)
2048 fn print_expr_unary(&mut self,
2050 expr: &ast::Expr) -> io::Result<()> {
2051 self.s.word(ast::UnOp::to_string(op))?;
2052 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
2055 fn print_expr_addr_of(&mut self,
2056 mutability: ast::Mutability,
2057 expr: &ast::Expr) -> io::Result<()> {
2059 self.print_mutability(mutability)?;
2060 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
2063 pub fn print_expr(&mut self, expr: &ast::Expr) -> io::Result<()> {
2064 self.print_expr_outer_attr_style(expr, true)
2067 fn print_expr_outer_attr_style(&mut self,
2069 is_inline: bool) -> io::Result<()> {
2070 self.maybe_print_comment(expr.span.lo())?;
2072 let attrs = &expr.attrs;
2074 self.print_outer_attributes_inline(attrs)?;
2076 self.print_outer_attributes(attrs)?;
2079 self.ibox(INDENT_UNIT)?;
2080 self.ann.pre(self, AnnNode::Expr(expr))?;
2082 ast::ExprKind::Box(ref expr) => {
2083 self.word_space("box")?;
2084 self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)?;
2086 ast::ExprKind::ObsoleteInPlace(ref place, ref expr) => {
2087 let prec = AssocOp::ObsoleteInPlace.precedence() as i8;
2088 self.print_expr_maybe_paren(place, prec + 1)?;
2090 self.word_space("<-")?;
2091 self.print_expr_maybe_paren(expr, prec)?;
2093 ast::ExprKind::Array(ref exprs) => {
2094 self.print_expr_vec(&exprs[..], attrs)?;
2096 ast::ExprKind::Repeat(ref element, ref count) => {
2097 self.print_expr_repeat(element, count, attrs)?;
2099 ast::ExprKind::Struct(ref path, ref fields, ref wth) => {
2100 self.print_expr_struct(path, &fields[..], wth, attrs)?;
2102 ast::ExprKind::Tup(ref exprs) => {
2103 self.print_expr_tup(&exprs[..], attrs)?;
2105 ast::ExprKind::Call(ref func, ref args) => {
2106 self.print_expr_call(func, &args[..])?;
2108 ast::ExprKind::MethodCall(ref segment, ref args) => {
2109 self.print_expr_method_call(segment, &args[..])?;
2111 ast::ExprKind::Binary(op, ref lhs, ref rhs) => {
2112 self.print_expr_binary(op, lhs, rhs)?;
2114 ast::ExprKind::Unary(op, ref expr) => {
2115 self.print_expr_unary(op, expr)?;
2117 ast::ExprKind::AddrOf(m, ref expr) => {
2118 self.print_expr_addr_of(m, expr)?;
2120 ast::ExprKind::Lit(ref lit) => {
2121 self.print_literal(lit)?;
2123 ast::ExprKind::Cast(ref expr, ref ty) => {
2124 let prec = AssocOp::As.precedence() as i8;
2125 self.print_expr_maybe_paren(expr, prec)?;
2127 self.word_space("as")?;
2128 self.print_type(ty)?;
2130 ast::ExprKind::Type(ref expr, ref ty) => {
2131 let prec = AssocOp::Colon.precedence() as i8;
2132 self.print_expr_maybe_paren(expr, prec)?;
2133 self.word_space(":")?;
2134 self.print_type(ty)?;
2136 ast::ExprKind::If(ref test, ref blk, ref elseopt) => {
2137 self.print_if(test, blk, elseopt.as_ref().map(|e| &**e))?;
2139 ast::ExprKind::IfLet(ref pats, ref expr, ref blk, ref elseopt) => {
2140 self.print_if_let(pats, expr, blk, elseopt.as_ref().map(|e| &**e))?;
2142 ast::ExprKind::While(ref test, ref blk, opt_label) => {
2143 if let Some(label) = opt_label {
2144 self.print_ident(label.ident)?;
2145 self.word_space(":")?;
2147 self.head("while")?;
2148 self.print_expr_as_cond(test)?;
2150 self.print_block_with_attrs(blk, attrs)?;
2152 ast::ExprKind::WhileLet(ref pats, ref expr, ref blk, opt_label) => {
2153 if let Some(label) = opt_label {
2154 self.print_ident(label.ident)?;
2155 self.word_space(":")?;
2157 self.head("while let")?;
2158 self.print_pats(pats)?;
2160 self.word_space("=")?;
2161 self.print_expr_as_cond(expr)?;
2163 self.print_block_with_attrs(blk, attrs)?;
2165 ast::ExprKind::ForLoop(ref pat, ref iter, ref blk, opt_label) => {
2166 if let Some(label) = opt_label {
2167 self.print_ident(label.ident)?;
2168 self.word_space(":")?;
2171 self.print_pat(pat)?;
2173 self.word_space("in")?;
2174 self.print_expr_as_cond(iter)?;
2176 self.print_block_with_attrs(blk, attrs)?;
2178 ast::ExprKind::Loop(ref blk, opt_label) => {
2179 if let Some(label) = opt_label {
2180 self.print_ident(label.ident)?;
2181 self.word_space(":")?;
2185 self.print_block_with_attrs(blk, attrs)?;
2187 ast::ExprKind::Match(ref expr, ref arms) => {
2188 self.cbox(INDENT_UNIT)?;
2190 self.word_nbsp("match")?;
2191 self.print_expr_as_cond(expr)?;
2194 self.print_inner_attributes_no_trailing_hardbreak(attrs)?;
2196 self.print_arm(arm)?;
2198 self.bclose_(expr.span, INDENT_UNIT)?;
2200 ast::ExprKind::Closure(
2201 capture_clause, asyncness, movability, ref decl, ref body, _) => {
2202 self.print_movability(movability)?;
2203 self.print_asyncness(asyncness)?;
2204 self.print_capture_clause(capture_clause)?;
2206 self.print_fn_block_args(decl)?;
2208 self.print_expr(body)?;
2209 self.end()?; // need to close a box
2211 // a box will be closed by print_expr, but we didn't want an overall
2212 // wrapper so we closed the corresponding opening. so create an
2213 // empty box to satisfy the close.
2216 ast::ExprKind::Block(ref blk, opt_label) => {
2217 if let Some(label) = opt_label {
2218 self.print_ident(label.ident)?;
2219 self.word_space(":")?;
2221 // containing cbox, will be closed by print-block at }
2222 self.cbox(INDENT_UNIT)?;
2223 // head-box, will be closed by print-block after {
2225 self.print_block_with_attrs(blk, attrs)?;
2227 ast::ExprKind::Async(capture_clause, _, ref blk) => {
2228 self.word_nbsp("async")?;
2229 self.print_capture_clause(capture_clause)?;
2231 // cbox/ibox in analogy to the `ExprKind::Block` arm above
2232 self.cbox(INDENT_UNIT)?;
2234 self.print_block_with_attrs(blk, attrs)?;
2236 ast::ExprKind::Assign(ref lhs, ref rhs) => {
2237 let prec = AssocOp::Assign.precedence() as i8;
2238 self.print_expr_maybe_paren(lhs, prec + 1)?;
2240 self.word_space("=")?;
2241 self.print_expr_maybe_paren(rhs, prec)?;
2243 ast::ExprKind::AssignOp(op, ref lhs, ref rhs) => {
2244 let prec = AssocOp::Assign.precedence() as i8;
2245 self.print_expr_maybe_paren(lhs, prec + 1)?;
2247 self.s.word(op.node.to_string())?;
2248 self.word_space("=")?;
2249 self.print_expr_maybe_paren(rhs, prec)?;
2251 ast::ExprKind::Field(ref expr, ident) => {
2252 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
2254 self.print_ident(ident)?;
2256 ast::ExprKind::Index(ref expr, ref index) => {
2257 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
2259 self.print_expr(index)?;
2262 ast::ExprKind::Range(ref start, ref end, limits) => {
2263 // Special case for `Range`. `AssocOp` claims that `Range` has higher precedence
2264 // than `Assign`, but `x .. x = x` gives a parse error instead of `x .. (x = x)`.
2265 // Here we use a fake precedence value so that any child with lower precedence than
2266 // a "normal" binop gets parenthesized. (`LOr` is the lowest-precedence binop.)
2267 let fake_prec = AssocOp::LOr.precedence() as i8;
2268 if let Some(ref e) = *start {
2269 self.print_expr_maybe_paren(e, fake_prec)?;
2271 if limits == ast::RangeLimits::HalfOpen {
2274 self.s.word("..=")?;
2276 if let Some(ref e) = *end {
2277 self.print_expr_maybe_paren(e, fake_prec)?;
2280 ast::ExprKind::Path(None, ref path) => {
2281 self.print_path(path, true, 0)?
2283 ast::ExprKind::Path(Some(ref qself), ref path) => {
2284 self.print_qpath(path, qself, true)?
2286 ast::ExprKind::Break(opt_label, ref opt_expr) => {
2287 self.s.word("break")?;
2289 if let Some(label) = opt_label {
2290 self.print_ident(label.ident)?;
2293 if let Some(ref expr) = *opt_expr {
2294 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2298 ast::ExprKind::Continue(opt_label) => {
2299 self.s.word("continue")?;
2301 if let Some(label) = opt_label {
2302 self.print_ident(label.ident)?;
2306 ast::ExprKind::Ret(ref result) => {
2307 self.s.word("return")?;
2308 if let Some(ref expr) = *result {
2310 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2313 ast::ExprKind::InlineAsm(ref a) => {
2314 self.s.word("asm!")?;
2316 self.print_string(&a.asm.as_str(), a.asm_str_style)?;
2317 self.word_space(":")?;
2319 self.commasep(Inconsistent, &a.outputs, |s, out| {
2320 let constraint = out.constraint.as_str();
2321 let mut ch = constraint.chars();
2323 Some('=') if out.is_rw => {
2324 s.print_string(&format!("+{}", ch.as_str()),
2325 ast::StrStyle::Cooked)?
2327 _ => s.print_string(&constraint, ast::StrStyle::Cooked)?
2330 s.print_expr(&out.expr)?;
2335 self.word_space(":")?;
2337 self.commasep(Inconsistent, &a.inputs, |s, &(co, ref o)| {
2338 s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
2345 self.word_space(":")?;
2347 self.commasep(Inconsistent, &a.clobbers,
2349 s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
2353 let mut options = vec![];
2355 options.push("volatile");
2358 options.push("alignstack");
2360 if a.dialect == ast::AsmDialect::Intel {
2361 options.push("intel");
2364 if !options.is_empty() {
2366 self.word_space(":")?;
2367 self.commasep(Inconsistent, &options,
2369 s.print_string(co, ast::StrStyle::Cooked)?;
2376 ast::ExprKind::Mac(ref m) => self.print_mac(m)?,
2377 ast::ExprKind::Paren(ref e) => {
2379 self.print_inner_attributes_inline(attrs)?;
2380 self.print_expr(e)?;
2383 ast::ExprKind::Yield(ref e) => {
2384 self.s.word("yield")?;
2388 self.print_expr_maybe_paren(expr, parser::PREC_JUMP)?;
2393 ast::ExprKind::Try(ref e) => {
2394 self.print_expr_maybe_paren(e, parser::PREC_POSTFIX)?;
2397 ast::ExprKind::TryBlock(ref blk) => {
2400 self.print_block_with_attrs(blk, attrs)?
2403 self.ann.post(self, AnnNode::Expr(expr))?;
2407 pub fn print_local_decl(&mut self, loc: &ast::Local) -> io::Result<()> {
2408 self.print_pat(&loc.pat)?;
2409 if let Some(ref ty) = loc.ty {
2410 self.word_space(":")?;
2411 self.print_type(ty)?;
2416 pub fn print_ident(&mut self, ident: ast::Ident) -> io::Result<()> {
2417 if ident.is_raw_guess() {
2418 self.s.word(&format!("r#{}", ident))?;
2420 self.s.word(&ident.as_str())?;
2422 self.ann.post(self, AnnNode::Ident(&ident))
2425 pub fn print_usize(&mut self, i: usize) -> io::Result<()> {
2426 self.s.word(&i.to_string())
2429 pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
2430 self.s.word(&name.as_str())?;
2431 self.ann.post(self, AnnNode::Name(&name))
2434 pub fn print_for_decl(&mut self, loc: &ast::Local,
2435 coll: &ast::Expr) -> io::Result<()> {
2436 self.print_local_decl(loc)?;
2438 self.word_space("in")?;
2439 self.print_expr(coll)
2442 fn print_path(&mut self,
2444 colons_before_params: bool,
2448 self.maybe_print_comment(path.span.lo())?;
2450 for (i, segment) in path.segments[..path.segments.len() - depth].iter().enumerate() {
2454 self.print_path_segment(segment, colons_before_params)?;
2460 fn print_path_segment(&mut self,
2461 segment: &ast::PathSegment,
2462 colons_before_params: bool)
2465 if segment.ident.name != keywords::CrateRoot.name() &&
2466 segment.ident.name != keywords::DollarCrate.name() {
2467 self.print_ident(segment.ident)?;
2468 if let Some(ref args) = segment.args {
2469 self.print_generic_args(args, colons_before_params)?;
2471 } else if segment.ident.name == keywords::DollarCrate.name() {
2472 self.print_dollar_crate(segment.ident.span.ctxt())?;
2477 fn print_qpath(&mut self,
2480 colons_before_params: bool)
2484 self.print_type(&qself.ty)?;
2485 if qself.position > 0 {
2487 self.word_space("as")?;
2488 let depth = path.segments.len() - qself.position;
2489 self.print_path(path, false, depth)?;
2493 let item_segment = path.segments.last().unwrap();
2494 self.print_ident(item_segment.ident)?;
2495 match item_segment.args {
2496 Some(ref args) => self.print_generic_args(args, colons_before_params),
2501 fn print_generic_args(&mut self,
2502 args: &ast::GenericArgs,
2503 colons_before_params: bool)
2506 if colons_before_params {
2511 ast::GenericArgs::AngleBracketed(ref data) => {
2514 self.commasep(Inconsistent, &data.args, |s, generic_arg| {
2515 s.print_generic_arg(generic_arg)
2518 let mut comma = data.args.len() != 0;
2520 for binding in data.bindings.iter() {
2522 self.word_space(",")?
2524 self.print_ident(binding.ident)?;
2526 self.word_space("=")?;
2527 self.print_type(&binding.ty)?;
2534 ast::GenericArgs::Parenthesized(ref data) => {
2539 |s, ty| s.print_type(ty))?;
2542 if let Some(ref ty) = data.output {
2543 self.space_if_not_bol()?;
2544 self.word_space("->")?;
2545 self.print_type(ty)?;
2553 pub fn print_pat(&mut self, pat: &ast::Pat) -> io::Result<()> {
2554 self.maybe_print_comment(pat.span.lo())?;
2555 self.ann.pre(self, AnnNode::Pat(pat))?;
2556 /* Pat isn't normalized, but the beauty of it
2557 is that it doesn't matter */
2559 PatKind::Wild => self.s.word("_")?,
2560 PatKind::Ident(binding_mode, ident, ref sub) => {
2561 match binding_mode {
2562 ast::BindingMode::ByRef(mutbl) => {
2563 self.word_nbsp("ref")?;
2564 self.print_mutability(mutbl)?;
2566 ast::BindingMode::ByValue(ast::Mutability::Immutable) => {}
2567 ast::BindingMode::ByValue(ast::Mutability::Mutable) => {
2568 self.word_nbsp("mut")?;
2571 self.print_ident(ident)?;
2572 if let Some(ref p) = *sub {
2577 PatKind::TupleStruct(ref path, ref elts, ddpos) => {
2578 self.print_path(path, true, 0)?;
2580 if let Some(ddpos) = ddpos {
2581 self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?;
2583 self.word_space(",")?;
2586 if ddpos != elts.len() {
2588 self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?;
2591 self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?;
2595 PatKind::Path(None, ref path) => {
2596 self.print_path(path, true, 0)?;
2598 PatKind::Path(Some(ref qself), ref path) => {
2599 self.print_qpath(path, qself, false)?;
2601 PatKind::Struct(ref path, ref fields, etc) => {
2602 self.print_path(path, true, 0)?;
2604 self.word_space("{")?;
2606 Consistent, &fields[..],
2608 s.cbox(INDENT_UNIT)?;
2609 if !f.node.is_shorthand {
2610 s.print_ident(f.node.ident)?;
2613 s.print_pat(&f.node.pat)?;
2616 |f| f.node.pat.span)?;
2618 if !fields.is_empty() { self.word_space(",")?; }
2624 PatKind::Tuple(ref elts, ddpos) => {
2626 if let Some(ddpos) = ddpos {
2627 self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(p))?;
2629 self.word_space(",")?;
2632 if ddpos != elts.len() {
2634 self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(p))?;
2637 self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(p))?;
2638 if elts.len() == 1 {
2644 PatKind::Box(ref inner) => {
2645 self.s.word("box ")?;
2646 self.print_pat(inner)?;
2648 PatKind::Ref(ref inner, mutbl) => {
2650 if mutbl == ast::Mutability::Mutable {
2651 self.s.word("mut ")?;
2653 self.print_pat(inner)?;
2655 PatKind::Lit(ref e) => self.print_expr(&**e)?,
2656 PatKind::Range(ref begin, ref end, Spanned { node: ref end_kind, .. }) => {
2657 self.print_expr(begin)?;
2660 RangeEnd::Included(RangeSyntax::DotDotDot) => self.s.word("...")?,
2661 RangeEnd::Included(RangeSyntax::DotDotEq) => self.s.word("..=")?,
2662 RangeEnd::Excluded => self.s.word("..")?,
2664 self.print_expr(end)?;
2666 PatKind::Slice(ref before, ref slice, ref after) => {
2668 self.commasep(Inconsistent,
2670 |s, p| s.print_pat(p))?;
2671 if let Some(ref p) = *slice {
2672 if !before.is_empty() { self.word_space(",")?; }
2673 if let PatKind::Wild = p.node {
2679 if !after.is_empty() { self.word_space(",")?; }
2681 self.commasep(Inconsistent,
2683 |s, p| s.print_pat(p))?;
2686 PatKind::Paren(ref inner) => {
2688 self.print_pat(inner)?;
2691 PatKind::Mac(ref m) => self.print_mac(m)?,
2693 self.ann.post(self, AnnNode::Pat(pat))
2696 fn print_pats(&mut self, pats: &[P<ast::Pat>]) -> io::Result<()> {
2697 let mut first = true;
2703 self.word_space("|")?;
2710 fn print_arm(&mut self, arm: &ast::Arm) -> io::Result<()> {
2711 // I have no idea why this check is necessary, but here it
2713 if arm.attrs.is_empty() {
2716 self.cbox(INDENT_UNIT)?;
2718 self.maybe_print_comment(arm.pats[0].span.lo())?;
2719 self.print_outer_attributes(&arm.attrs)?;
2720 self.print_pats(&arm.pats)?;
2722 if let Some(ref g) = arm.guard {
2724 ast::Guard::If(ref e) => {
2725 self.word_space("if")?;
2726 self.print_expr(e)?;
2731 self.word_space("=>")?;
2733 match arm.body.node {
2734 ast::ExprKind::Block(ref blk, opt_label) => {
2735 if let Some(label) = opt_label {
2736 self.print_ident(label.ident)?;
2737 self.word_space(":")?;
2740 // the block will close the pattern's ibox
2741 self.print_block_unclosed_indent(blk, INDENT_UNIT)?;
2743 // If it is a user-provided unsafe block, print a comma after it
2744 if let BlockCheckMode::Unsafe(ast::UserProvided) = blk.rules {
2749 self.end()?; // close the ibox for the pattern
2750 self.print_expr(&arm.body)?;
2754 self.end() // close enclosing cbox
2757 fn print_explicit_self(&mut self, explicit_self: &ast::ExplicitSelf) -> io::Result<()> {
2758 match explicit_self.node {
2759 SelfKind::Value(m) => {
2760 self.print_mutability(m)?;
2763 SelfKind::Region(ref lt, m) => {
2765 self.print_opt_lifetime(lt)?;
2766 self.print_mutability(m)?;
2769 SelfKind::Explicit(ref typ, m) => {
2770 self.print_mutability(m)?;
2771 self.s.word("self")?;
2772 self.word_space(":")?;
2773 self.print_type(typ)
2778 pub fn print_fn(&mut self,
2780 header: ast::FnHeader,
2781 name: Option<ast::Ident>,
2782 generics: &ast::Generics,
2783 vis: &ast::Visibility) -> io::Result<()> {
2784 self.print_fn_header_info(header, vis)?;
2786 if let Some(name) = name {
2788 self.print_ident(name)?;
2790 self.print_generic_params(&generics.params)?;
2791 self.print_fn_args_and_ret(decl)?;
2792 self.print_where_clause(&generics.where_clause)
2795 pub fn print_fn_args_and_ret(&mut self, decl: &ast::FnDecl)
2798 self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, false))?;
2800 self.s.word(", ...")?;
2804 self.print_fn_output(decl)
2807 pub fn print_fn_block_args(
2812 self.commasep(Inconsistent, &decl.inputs, |s, arg| s.print_arg(arg, true))?;
2815 if let ast::FunctionRetTy::Default(..) = decl.output {
2819 self.space_if_not_bol()?;
2820 self.word_space("->")?;
2822 ast::FunctionRetTy::Ty(ref ty) => {
2823 self.print_type(ty)?;
2824 self.maybe_print_comment(ty.span.lo())
2826 ast::FunctionRetTy::Default(..) => unreachable!(),
2830 pub fn print_movability(&mut self, movability: ast::Movability)
2833 ast::Movability::Static => self.word_space("static"),
2834 ast::Movability::Movable => Ok(()),
2838 pub fn print_asyncness(&mut self, asyncness: ast::IsAsync)
2840 if asyncness.is_async() {
2841 self.word_nbsp("async")?;
2846 pub fn print_capture_clause(&mut self, capture_clause: ast::CaptureBy)
2848 match capture_clause {
2849 ast::CaptureBy::Value => self.word_space("move"),
2850 ast::CaptureBy::Ref => Ok(()),
2854 pub fn print_type_bounds(&mut self,
2856 bounds: &[ast::GenericBound])
2858 if !bounds.is_empty() {
2859 self.s.word(prefix)?;
2860 let mut first = true;
2861 for bound in bounds {
2862 if !(first && prefix.is_empty()) {
2868 self.word_space("+")?;
2872 GenericBound::Trait(tref, modifier) => {
2873 if modifier == &TraitBoundModifier::Maybe {
2876 self.print_poly_trait_ref(tref)?;
2878 GenericBound::Outlives(lt) => self.print_lifetime(*lt)?,
2885 pub fn print_lifetime(&mut self, lifetime: ast::Lifetime) -> io::Result<()> {
2886 self.print_name(lifetime.ident.name)
2889 pub fn print_lifetime_bounds(&mut self, lifetime: ast::Lifetime, bounds: &ast::GenericBounds)
2892 self.print_lifetime(lifetime)?;
2893 if !bounds.is_empty() {
2895 for (i, bound) in bounds.iter().enumerate() {
2897 self.s.word(" + ")?;
2900 ast::GenericBound::Outlives(lt) => self.print_lifetime(*lt)?,
2908 pub fn print_generic_params(
2910 generic_params: &[ast::GenericParam]
2911 ) -> io::Result<()> {
2912 if generic_params.is_empty() {
2918 self.commasep(Inconsistent, &generic_params, |s, param| {
2920 ast::GenericParamKind::Lifetime => {
2921 s.print_outer_attributes_inline(¶m.attrs)?;
2922 let lt = ast::Lifetime { id: param.id, ident: param.ident };
2923 s.print_lifetime_bounds(lt, ¶m.bounds)
2925 ast::GenericParamKind::Type { ref default } => {
2926 s.print_outer_attributes_inline(¶m.attrs)?;
2927 s.print_ident(param.ident)?;
2928 s.print_type_bounds(":", ¶m.bounds)?;
2930 Some(ref default) => {
2933 s.print_type(default)
2945 pub fn print_where_clause(&mut self, where_clause: &ast::WhereClause)
2947 if where_clause.predicates.is_empty() {
2952 self.word_space("where")?;
2954 for (i, predicate) in where_clause.predicates.iter().enumerate() {
2956 self.word_space(",")?;
2960 ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate {
2961 ref bound_generic_params,
2966 self.print_formal_generic_params(bound_generic_params)?;
2967 self.print_type(bounded_ty)?;
2968 self.print_type_bounds(":", bounds)?;
2970 ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate{ref lifetime,
2973 self.print_lifetime_bounds(*lifetime, bounds)?;
2975 ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{ref lhs_ty,
2978 self.print_type(lhs_ty)?;
2980 self.word_space("=")?;
2981 self.print_type(rhs_ty)?;
2989 pub fn print_use_tree(&mut self, tree: &ast::UseTree) -> io::Result<()> {
2991 ast::UseTreeKind::Simple(rename, ..) => {
2992 self.print_path(&tree.prefix, false, 0)?;
2993 if let Some(rename) = rename {
2995 self.word_space("as")?;
2996 self.print_ident(rename)?;
2999 ast::UseTreeKind::Glob => {
3000 if !tree.prefix.segments.is_empty() {
3001 self.print_path(&tree.prefix, false, 0)?;
3006 ast::UseTreeKind::Nested(ref items) => {
3007 if tree.prefix.segments.is_empty() {
3010 self.print_path(&tree.prefix, false, 0)?;
3011 self.s.word("::{")?;
3013 self.commasep(Inconsistent, &items[..], |this, &(ref tree, _)| {
3014 this.print_use_tree(tree)
3023 pub fn print_mutability(&mut self,
3024 mutbl: ast::Mutability) -> io::Result<()> {
3026 ast::Mutability::Mutable => self.word_nbsp("mut"),
3027 ast::Mutability::Immutable => Ok(()),
3031 pub fn print_mt(&mut self, mt: &ast::MutTy) -> io::Result<()> {
3032 self.print_mutability(mt.mutbl)?;
3033 self.print_type(&mt.ty)
3036 pub fn print_arg(&mut self, input: &ast::Arg, is_closure: bool) -> io::Result<()> {
3037 self.ibox(INDENT_UNIT)?;
3038 match input.ty.node {
3039 ast::TyKind::Infer if is_closure => self.print_pat(&input.pat)?,
3041 if let Some(eself) = input.to_self() {
3042 self.print_explicit_self(&eself)?;
3044 let invalid = if let PatKind::Ident(_, ident, _) = input.pat.node {
3045 ident.name == keywords::Invalid.name()
3050 self.print_pat(&input.pat)?;
3054 self.print_type(&input.ty)?;
3061 pub fn print_fn_output(&mut self, decl: &ast::FnDecl) -> io::Result<()> {
3062 if let ast::FunctionRetTy::Default(..) = decl.output {
3066 self.space_if_not_bol()?;
3067 self.ibox(INDENT_UNIT)?;
3068 self.word_space("->")?;
3070 ast::FunctionRetTy::Default(..) => unreachable!(),
3071 ast::FunctionRetTy::Ty(ref ty) =>
3072 self.print_type(ty)?
3077 ast::FunctionRetTy::Ty(ref output) => self.maybe_print_comment(output.span.lo()),
3082 pub fn print_ty_fn(&mut self,
3084 unsafety: ast::Unsafety,
3086 name: Option<ast::Ident>,
3087 generic_params: &[ast::GenericParam])
3089 self.ibox(INDENT_UNIT)?;
3090 if !generic_params.is_empty() {
3091 self.s.word("for")?;
3092 self.print_generic_params(generic_params)?;
3094 let generics = ast::Generics {
3096 where_clause: ast::WhereClause {
3097 id: ast::DUMMY_NODE_ID,
3098 predicates: Vec::new(),
3099 span: syntax_pos::DUMMY_SP,
3101 span: syntax_pos::DUMMY_SP,
3104 ast::FnHeader { unsafety, abi, ..ast::FnHeader::default() },
3107 &source_map::dummy_spanned(ast::VisibilityKind::Inherited))?;
3111 pub fn maybe_print_trailing_comment(&mut self, span: syntax_pos::Span,
3112 next_pos: Option<BytePos>)
3114 let cm = match self.cm {
3118 if let Some(ref cmnt) = self.next_comment() {
3119 if cmnt.style != comments::Trailing { return Ok(()) }
3120 let span_line = cm.lookup_char_pos(span.hi());
3121 let comment_line = cm.lookup_char_pos(cmnt.pos);
3122 let next = next_pos.unwrap_or(cmnt.pos + BytePos(1));
3123 if span.hi() < cmnt.pos && cmnt.pos < next && span_line.line == comment_line.line {
3124 self.print_comment(cmnt)?;
3130 pub fn print_remaining_comments(&mut self) -> io::Result<()> {
3131 // If there aren't any remaining comments, then we need to manually
3132 // make sure there is a line break at the end.
3133 if self.next_comment().is_none() {
3134 self.s.hardbreak()?;
3136 while let Some(ref cmnt) = self.next_comment() {
3137 self.print_comment(cmnt)?;
3142 pub fn print_opt_abi_and_extern_if_nondefault(&mut self,
3143 opt_abi: Option<Abi>)
3146 Some(Abi::Rust) => Ok(()),
3148 self.word_nbsp("extern")?;
3149 self.word_nbsp(&abi.to_string())
3155 pub fn print_extern_opt_abi(&mut self,
3156 opt_abi: Option<Abi>) -> io::Result<()> {
3159 self.word_nbsp("extern")?;
3160 self.word_nbsp(&abi.to_string())
3166 pub fn print_fn_header_info(&mut self,
3167 header: ast::FnHeader,
3168 vis: &ast::Visibility) -> io::Result<()> {
3169 self.s.word(&visibility_qualified(vis, ""))?;
3171 match header.constness.node {
3172 ast::Constness::NotConst => {}
3173 ast::Constness::Const => self.word_nbsp("const")?
3176 self.print_asyncness(header.asyncness)?;
3177 self.print_unsafety(header.unsafety)?;
3179 if header.abi != Abi::Rust {
3180 self.word_nbsp("extern")?;
3181 self.word_nbsp(&header.abi.to_string())?;
3187 pub fn print_unsafety(&mut self, s: ast::Unsafety) -> io::Result<()> {
3189 ast::Unsafety::Normal => Ok(()),
3190 ast::Unsafety::Unsafe => self.word_nbsp("unsafe"),
3194 pub fn print_is_auto(&mut self, s: ast::IsAuto) -> io::Result<()> {
3196 ast::IsAuto::Yes => self.word_nbsp("auto"),
3197 ast::IsAuto::No => Ok(()),
3212 fn test_fun_to_string() {
3214 let abba_ident = ast::Ident::from_str("abba");
3216 let decl = ast::FnDecl {
3218 output: ast::FunctionRetTy::Default(syntax_pos::DUMMY_SP),
3221 let generics = ast::Generics::default();
3226 unsafety: ast::Unsafety::Normal,
3227 constness: source_map::dummy_spanned(ast::Constness::NotConst),
3228 asyncness: ast::IsAsync::NotAsync,
3240 fn test_variant_to_string() {
3242 let ident = ast::Ident::from_str("principal_skinner");
3244 let var = source_map::respan(syntax_pos::DUMMY_SP, ast::Variant_ {
3247 // making this up as I go.... ?
3248 data: ast::VariantData::Unit(ast::DUMMY_NODE_ID),
3252 let varstr = variant_to_string(&var);
3253 assert_eq!(varstr, "principal_skinner");