// Copyright 2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. pub use self::AnnNode::*; use syntax::abi::Abi; use syntax::ast; use syntax::codemap::{CodeMap, Spanned}; use syntax::parse::ParseSess; use syntax::parse::lexer::comments; use syntax::print::pp::{self, break_offset, word, space, hardbreak}; use syntax::print::pp::{Breaks, eof}; use syntax::print::pp::Breaks::{Consistent, Inconsistent}; use syntax::print::pprust::{self as ast_pp, PrintState}; use syntax::ptr::P; use syntax::symbol::keywords; use syntax_pos::{self, BytePos}; use hir; use hir::{PatKind, RegionTyParamBound, TraitTyParamBound, TraitBoundModifier, RangeEnd}; use std::cell::Cell; use std::io::{self, Write, Read}; pub enum AnnNode<'a> { NodeName(&'a ast::Name), NodeBlock(&'a hir::Block), NodeItem(&'a hir::Item), NodeSubItem(ast::NodeId), NodeExpr(&'a hir::Expr), NodePat(&'a hir::Pat), } pub enum Nested { Item(hir::ItemId), TraitItem(hir::TraitItemId), ImplItem(hir::ImplItemId), Body(hir::BodyId), BodyArgPat(hir::BodyId, usize) } pub trait PpAnn { fn nested(&self, _state: &mut State, _nested: Nested) -> io::Result<()> { Ok(()) } fn pre(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) } fn post(&self, _state: &mut State, _node: AnnNode) -> io::Result<()> { Ok(()) } } pub struct NoAnn; impl PpAnn for NoAnn {} pub const NO_ANN: &'static PpAnn = &NoAnn; impl PpAnn for hir::Crate { fn nested(&self, state: &mut State, nested: Nested) -> io::Result<()> { match nested { Nested::Item(id) => state.print_item(self.item(id.id)), Nested::TraitItem(id) => state.print_trait_item(self.trait_item(id)), Nested::ImplItem(id) => state.print_impl_item(self.impl_item(id)), Nested::Body(id) => state.print_expr(&self.body(id).value), Nested::BodyArgPat(id, i) => state.print_pat(&self.body(id).arguments[i].pat) } } } pub struct State<'a> { pub s: pp::Printer<'a>, cm: Option<&'a CodeMap>, comments: Option>, literals: Option>, cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral, boxes: Vec, ann: &'a (PpAnn + 'a), } impl<'a> PrintState<'a> for State<'a> { fn writer(&mut self) -> &mut pp::Printer<'a> { &mut self.s } fn boxes(&mut self) -> &mut Vec { &mut self.boxes } fn comments(&mut self) -> &mut Option> { &mut self.comments } fn cur_cmnt_and_lit(&mut self) -> &mut ast_pp::CurrentCommentAndLiteral { &mut self.cur_cmnt_and_lit } fn literals(&self) -> &Option> { &self.literals } } #[allow(non_upper_case_globals)] pub const indent_unit: usize = 4; #[allow(non_upper_case_globals)] pub const default_columns: usize = 78; /// Requires you to pass an input filename and reader so that /// it can scan the input text for comments and literals to /// copy forward. pub fn print_crate<'a>(cm: &'a CodeMap, sess: &ParseSess, krate: &hir::Crate, filename: String, input: &mut Read, out: Box, ann: &'a PpAnn, is_expanded: bool) -> io::Result<()> { let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded); // When printing the AST, we sometimes need to inject `#[no_std]` here. // Since you can't compile the HIR, it's not necessary. s.print_mod(&krate.module, &krate.attrs)?; s.print_remaining_comments()?; eof(&mut s.s) } impl<'a> State<'a> { pub fn new_from_input(cm: &'a CodeMap, sess: &ParseSess, filename: String, input: &mut Read, out: Box, ann: &'a PpAnn, is_expanded: bool) -> State<'a> { let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input); State::new(cm, out, ann, Some(cmnts), // If the code is post expansion, don't use the table of // literals, since it doesn't correspond with the literals // in the AST anymore. if is_expanded { None } else { Some(lits) }) } pub fn new(cm: &'a CodeMap, out: Box, ann: &'a PpAnn, comments: Option>, literals: Option>) -> State<'a> { State { s: pp::mk_printer(out, default_columns), cm: Some(cm), comments: comments.clone(), literals: literals.clone(), cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral { cur_cmnt: 0, cur_lit: 0, }, boxes: Vec::new(), ann: ann, } } } pub fn to_string(ann: &PpAnn, f: F) -> String where F: FnOnce(&mut State) -> io::Result<()> { let mut wr = Vec::new(); { let mut printer = State { s: pp::mk_printer(Box::new(&mut wr), default_columns), cm: None, comments: None, literals: None, cur_cmnt_and_lit: ast_pp::CurrentCommentAndLiteral { cur_cmnt: 0, cur_lit: 0, }, boxes: Vec::new(), ann: ann, }; f(&mut printer).unwrap(); eof(&mut printer.s).unwrap(); } String::from_utf8(wr).unwrap() } pub fn visibility_qualified(vis: &hir::Visibility, w: &str) -> String { to_string(NO_ANN, |s| { s.print_visibility(vis)?; word(&mut s.s, w) }) } fn needs_parentheses(expr: &hir::Expr) -> bool { match expr.node { hir::ExprAssign(..) | hir::ExprBinary(..) | hir::ExprClosure(..) | hir::ExprAssignOp(..) | hir::ExprCast(..) | hir::ExprType(..) => true, _ => false, } } impl<'a> State<'a> { pub fn cbox(&mut self, u: usize) -> io::Result<()> { self.boxes.push(pp::Breaks::Consistent); pp::cbox(&mut self.s, u) } pub fn nbsp(&mut self) -> io::Result<()> { word(&mut self.s, " ") } pub fn word_nbsp(&mut self, w: &str) -> io::Result<()> { word(&mut self.s, w)?; self.nbsp() } pub fn head(&mut self, w: &str) -> io::Result<()> { // outer-box is consistent self.cbox(indent_unit)?; // head-box is inconsistent self.ibox(w.len() + 1)?; // keyword that starts the head if !w.is_empty() { self.word_nbsp(w)?; } Ok(()) } pub fn bopen(&mut self) -> io::Result<()> { word(&mut self.s, "{")?; self.end() // close the head-box } pub fn bclose_(&mut self, span: syntax_pos::Span, indented: usize) -> io::Result<()> { self.bclose_maybe_open(span, indented, true) } pub fn bclose_maybe_open(&mut self, span: syntax_pos::Span, indented: usize, close_box: bool) -> io::Result<()> { self.maybe_print_comment(span.hi)?; self.break_offset_if_not_bol(1, -(indented as isize))?; word(&mut self.s, "}")?; if close_box { self.end()?; // close the outer-box } Ok(()) } pub fn bclose(&mut self, span: syntax_pos::Span) -> io::Result<()> { self.bclose_(span, indent_unit) } pub fn in_cbox(&self) -> bool { match self.boxes.last() { Some(&last_box) => last_box == pp::Breaks::Consistent, None => false, } } pub fn space_if_not_bol(&mut self) -> io::Result<()> { if !self.is_bol() { space(&mut self.s)?; } Ok(()) } pub fn break_offset_if_not_bol(&mut self, n: usize, off: isize) -> io::Result<()> { if !self.is_bol() { break_offset(&mut self.s, n, off) } else { if off != 0 && self.s.last_token().is_hardbreak_tok() { // We do something pretty sketchy here: tuck the nonzero // offset-adjustment we were going to deposit along with the // break into the previous hardbreak. self.s.replace_last_token(pp::hardbreak_tok_offset(off)); } Ok(()) } } // Synthesizes a comment that was not textually present in the original source // file. pub fn synth_comment(&mut self, text: String) -> io::Result<()> { word(&mut self.s, "/*")?; space(&mut self.s)?; word(&mut self.s, &text[..])?; space(&mut self.s)?; word(&mut self.s, "*/") } pub fn commasep_cmnt(&mut self, b: Breaks, elts: &[T], mut op: F, mut get_span: G) -> io::Result<()> where F: FnMut(&mut State, &T) -> io::Result<()>, G: FnMut(&T) -> syntax_pos::Span { self.rbox(0, b)?; let len = elts.len(); let mut i = 0; for elt in elts { self.maybe_print_comment(get_span(elt).hi)?; op(self, elt)?; i += 1; if i < len { word(&mut self.s, ",")?; self.maybe_print_trailing_comment(get_span(elt), Some(get_span(&elts[i]).hi))?; self.space_if_not_bol()?; } } self.end() } pub fn commasep_exprs(&mut self, b: Breaks, exprs: &[hir::Expr]) -> io::Result<()> { self.commasep_cmnt(b, exprs, |s, e| s.print_expr(&e), |e| e.span) } pub fn print_mod(&mut self, _mod: &hir::Mod, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_inner_attributes(attrs)?; for &item_id in &_mod.item_ids { self.ann.nested(self, Nested::Item(item_id))?; } Ok(()) } pub fn print_foreign_mod(&mut self, nmod: &hir::ForeignMod, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_inner_attributes(attrs)?; for item in &nmod.items { self.print_foreign_item(item)?; } Ok(()) } pub fn print_opt_lifetime(&mut self, lifetime: &hir::Lifetime) -> io::Result<()> { if !lifetime.is_elided() { self.print_lifetime(lifetime)?; self.nbsp()?; } Ok(()) } pub fn print_type(&mut self, ty: &hir::Ty) -> io::Result<()> { self.maybe_print_comment(ty.span.lo)?; self.ibox(0)?; match ty.node { hir::TySlice(ref ty) => { word(&mut self.s, "[")?; self.print_type(&ty)?; word(&mut self.s, "]")?; } hir::TyPtr(ref mt) => { word(&mut self.s, "*")?; match mt.mutbl { hir::MutMutable => self.word_nbsp("mut")?, hir::MutImmutable => self.word_nbsp("const")?, } self.print_type(&mt.ty)?; } hir::TyRptr(ref lifetime, ref mt) => { word(&mut self.s, "&")?; self.print_opt_lifetime(lifetime)?; self.print_mt(mt)?; } hir::TyNever => { word(&mut self.s, "!")?; }, hir::TyTup(ref elts) => { self.popen()?; self.commasep(Inconsistent, &elts[..], |s, ty| s.print_type(&ty))?; if elts.len() == 1 { word(&mut self.s, ",")?; } self.pclose()?; } hir::TyBareFn(ref f) => { let generics = hir::Generics { lifetimes: f.lifetimes.clone(), ty_params: hir::HirVec::new(), where_clause: hir::WhereClause { id: ast::DUMMY_NODE_ID, predicates: hir::HirVec::new(), }, span: syntax_pos::DUMMY_SP, }; self.print_ty_fn(f.abi, f.unsafety, &f.decl, None, &generics)?; } hir::TyPath(ref qpath) => { self.print_qpath(qpath, false)? } hir::TyTraitObject(ref bounds, ref lifetime) => { let mut first = true; for bound in bounds { self.nbsp()?; if first { first = false; } else { self.word_space("+")?; } self.print_poly_trait_ref(bound)?; } if !lifetime.is_elided() { self.word_space("+")?; self.print_lifetime(lifetime)?; } } hir::TyImplTrait(ref bounds) => { self.print_bounds("impl ", &bounds[..])?; } hir::TyArray(ref ty, v) => { word(&mut self.s, "[")?; self.print_type(&ty)?; word(&mut self.s, "; ")?; self.ann.nested(self, Nested::Body(v))?; word(&mut self.s, "]")?; } hir::TyTypeof(e) => { word(&mut self.s, "typeof(")?; self.ann.nested(self, Nested::Body(e))?; word(&mut self.s, ")")?; } hir::TyInfer => { word(&mut self.s, "_")?; } } self.end() } pub fn print_foreign_item(&mut self, item: &hir::ForeignItem) -> io::Result<()> { self.hardbreak_if_not_bol()?; self.maybe_print_comment(item.span.lo)?; self.print_outer_attributes(&item.attrs)?; match item.node { hir::ForeignItemFn(ref decl, ref arg_names, ref generics) => { self.head("")?; self.print_fn(decl, hir::Unsafety::Normal, hir::Constness::NotConst, Abi::Rust, Some(item.name), generics, &item.vis, arg_names, None)?; self.end()?; // end head-ibox word(&mut self.s, ";")?; self.end() // end the outer fn box } hir::ForeignItemStatic(ref t, m) => { self.head(&visibility_qualified(&item.vis, "static"))?; if m { self.word_space("mut")?; } self.print_name(item.name)?; self.word_space(":")?; self.print_type(&t)?; word(&mut self.s, ";")?; self.end()?; // end the head-ibox self.end() // end the outer cbox } } } fn print_associated_const(&mut self, name: ast::Name, ty: &hir::Ty, default: Option, vis: &hir::Visibility) -> io::Result<()> { word(&mut self.s, &visibility_qualified(vis, ""))?; self.word_space("const")?; self.print_name(name)?; self.word_space(":")?; self.print_type(ty)?; if let Some(expr) = default { space(&mut self.s)?; self.word_space("=")?; self.ann.nested(self, Nested::Body(expr))?; } word(&mut self.s, ";") } fn print_associated_type(&mut self, name: ast::Name, bounds: Option<&hir::TyParamBounds>, ty: Option<&hir::Ty>) -> io::Result<()> { self.word_space("type")?; self.print_name(name)?; if let Some(bounds) = bounds { self.print_bounds(":", bounds)?; } if let Some(ty) = ty { space(&mut self.s)?; self.word_space("=")?; self.print_type(ty)?; } word(&mut self.s, ";") } /// Pretty-print an item pub fn print_item(&mut self, item: &hir::Item) -> io::Result<()> { self.hardbreak_if_not_bol()?; self.maybe_print_comment(item.span.lo)?; self.print_outer_attributes(&item.attrs)?; self.ann.pre(self, NodeItem(item))?; match item.node { hir::ItemExternCrate(ref optional_path) => { self.head(&visibility_qualified(&item.vis, "extern crate"))?; if let Some(p) = *optional_path { let val = p.as_str(); if val.contains("-") { self.print_string(&val, ast::StrStyle::Cooked)?; } else { self.print_name(p)?; } space(&mut self.s)?; word(&mut self.s, "as")?; space(&mut self.s)?; } self.print_name(item.name)?; word(&mut self.s, ";")?; self.end()?; // end inner head-block self.end()?; // end outer head-block } hir::ItemUse(ref path, kind) => { self.head(&visibility_qualified(&item.vis, "use"))?; self.print_path(path, false)?; match kind { hir::UseKind::Single => { if path.segments.last().unwrap().name != item.name { space(&mut self.s)?; self.word_space("as")?; self.print_name(item.name)?; } word(&mut self.s, ";")?; } hir::UseKind::Glob => word(&mut self.s, "::*;")?, hir::UseKind::ListStem => word(&mut self.s, "::{};")? } self.end()?; // end inner head-block self.end()?; // end outer head-block } hir::ItemStatic(ref ty, m, expr) => { self.head(&visibility_qualified(&item.vis, "static"))?; if m == hir::MutMutable { self.word_space("mut")?; } self.print_name(item.name)?; self.word_space(":")?; self.print_type(&ty)?; space(&mut self.s)?; self.end()?; // end the head-ibox self.word_space("=")?; self.ann.nested(self, Nested::Body(expr))?; word(&mut self.s, ";")?; self.end()?; // end the outer cbox } hir::ItemConst(ref ty, expr) => { self.head(&visibility_qualified(&item.vis, "const"))?; self.print_name(item.name)?; self.word_space(":")?; self.print_type(&ty)?; space(&mut self.s)?; self.end()?; // end the head-ibox self.word_space("=")?; self.ann.nested(self, Nested::Body(expr))?; word(&mut self.s, ";")?; self.end()?; // end the outer cbox } hir::ItemFn(ref decl, unsafety, constness, abi, ref typarams, body) => { self.head("")?; self.print_fn(decl, unsafety, constness, abi, Some(item.name), typarams, &item.vis, &[], Some(body))?; word(&mut self.s, " ")?; self.end()?; // need to close a box self.end()?; // need to close a box self.ann.nested(self, Nested::Body(body))?; } hir::ItemMod(ref _mod) => { self.head(&visibility_qualified(&item.vis, "mod"))?; self.print_name(item.name)?; self.nbsp()?; self.bopen()?; self.print_mod(_mod, &item.attrs)?; self.bclose(item.span)?; } hir::ItemForeignMod(ref nmod) => { self.head("extern")?; self.word_nbsp(&nmod.abi.to_string())?; self.bopen()?; self.print_foreign_mod(nmod, &item.attrs)?; self.bclose(item.span)?; } hir::ItemTy(ref ty, ref params) => { self.ibox(indent_unit)?; self.ibox(0)?; self.word_nbsp(&visibility_qualified(&item.vis, "type"))?; self.print_name(item.name)?; self.print_generics(params)?; self.end()?; // end the inner ibox self.print_where_clause(¶ms.where_clause)?; space(&mut self.s)?; self.word_space("=")?; self.print_type(&ty)?; word(&mut self.s, ";")?; self.end()?; // end the outer ibox } hir::ItemEnum(ref enum_definition, ref params) => { self.print_enum_def(enum_definition, params, item.name, item.span, &item.vis)?; } hir::ItemStruct(ref struct_def, ref generics) => { self.head(&visibility_qualified(&item.vis, "struct"))?; self.print_struct(struct_def, generics, item.name, item.span, true)?; } hir::ItemUnion(ref struct_def, ref generics) => { self.head(&visibility_qualified(&item.vis, "union"))?; self.print_struct(struct_def, generics, item.name, item.span, true)?; } hir::ItemDefaultImpl(unsafety, ref trait_ref) => { self.head("")?; self.print_visibility(&item.vis)?; self.print_unsafety(unsafety)?; self.word_nbsp("impl")?; self.print_trait_ref(trait_ref)?; space(&mut self.s)?; self.word_space("for")?; self.word_space("..")?; self.bopen()?; self.bclose(item.span)?; } hir::ItemImpl(unsafety, polarity, ref generics, ref opt_trait, ref ty, ref impl_items) => { self.head("")?; self.print_visibility(&item.vis)?; self.print_unsafety(unsafety)?; self.word_nbsp("impl")?; if generics.is_parameterized() { self.print_generics(generics)?; space(&mut self.s)?; } match polarity { hir::ImplPolarity::Negative => { word(&mut self.s, "!")?; } _ => {} } match opt_trait { &Some(ref t) => { self.print_trait_ref(t)?; space(&mut self.s)?; self.word_space("for")?; } &None => {} } self.print_type(&ty)?; self.print_where_clause(&generics.where_clause)?; space(&mut self.s)?; self.bopen()?; self.print_inner_attributes(&item.attrs)?; for impl_item in impl_items { self.ann.nested(self, Nested::ImplItem(impl_item.id))?; } self.bclose(item.span)?; } hir::ItemTrait(unsafety, ref generics, ref bounds, ref trait_items) => { self.head("")?; self.print_visibility(&item.vis)?; self.print_unsafety(unsafety)?; self.word_nbsp("trait")?; self.print_name(item.name)?; self.print_generics(generics)?; let mut real_bounds = Vec::with_capacity(bounds.len()); for b in bounds.iter() { if let TraitTyParamBound(ref ptr, hir::TraitBoundModifier::Maybe) = *b { space(&mut self.s)?; self.word_space("for ?")?; self.print_trait_ref(&ptr.trait_ref)?; } else { real_bounds.push(b.clone()); } } self.print_bounds(":", &real_bounds[..])?; self.print_where_clause(&generics.where_clause)?; word(&mut self.s, " ")?; self.bopen()?; for trait_item in trait_items { self.ann.nested(self, Nested::TraitItem(trait_item.id))?; } self.bclose(item.span)?; } } self.ann.post(self, NodeItem(item)) } pub fn print_trait_ref(&mut self, t: &hir::TraitRef) -> io::Result<()> { self.print_path(&t.path, false) } fn print_formal_lifetime_list(&mut self, lifetimes: &[hir::LifetimeDef]) -> io::Result<()> { if !lifetimes.is_empty() { word(&mut self.s, "for<")?; let mut comma = false; for lifetime_def in lifetimes { if comma { self.word_space(",")? } self.print_lifetime_def(lifetime_def)?; comma = true; } word(&mut self.s, ">")?; } Ok(()) } fn print_poly_trait_ref(&mut self, t: &hir::PolyTraitRef) -> io::Result<()> { self.print_formal_lifetime_list(&t.bound_lifetimes)?; self.print_trait_ref(&t.trait_ref) } pub fn print_enum_def(&mut self, enum_definition: &hir::EnumDef, generics: &hir::Generics, name: ast::Name, span: syntax_pos::Span, visibility: &hir::Visibility) -> io::Result<()> { self.head(&visibility_qualified(visibility, "enum"))?; self.print_name(name)?; self.print_generics(generics)?; self.print_where_clause(&generics.where_clause)?; space(&mut self.s)?; self.print_variants(&enum_definition.variants, span) } pub fn print_variants(&mut self, variants: &[hir::Variant], span: syntax_pos::Span) -> io::Result<()> { self.bopen()?; for v in variants { self.space_if_not_bol()?; self.maybe_print_comment(v.span.lo)?; self.print_outer_attributes(&v.node.attrs)?; self.ibox(indent_unit)?; self.print_variant(v)?; word(&mut self.s, ",")?; self.end()?; self.maybe_print_trailing_comment(v.span, None)?; } self.bclose(span) } pub fn print_visibility(&mut self, vis: &hir::Visibility) -> io::Result<()> { match *vis { hir::Public => self.word_nbsp("pub"), hir::Visibility::Crate => self.word_nbsp("pub(crate)"), hir::Visibility::Restricted { ref path, .. } => { word(&mut self.s, "pub(")?; self.print_path(path, false)?; self.word_nbsp(")") } hir::Inherited => Ok(()), } } pub fn print_struct(&mut self, struct_def: &hir::VariantData, generics: &hir::Generics, name: ast::Name, span: syntax_pos::Span, print_finalizer: bool) -> io::Result<()> { self.print_name(name)?; self.print_generics(generics)?; if !struct_def.is_struct() { if struct_def.is_tuple() { self.popen()?; self.commasep(Inconsistent, struct_def.fields(), |s, field| { s.maybe_print_comment(field.span.lo)?; s.print_outer_attributes(&field.attrs)?; s.print_visibility(&field.vis)?; s.print_type(&field.ty) })?; self.pclose()?; } self.print_where_clause(&generics.where_clause)?; if print_finalizer { word(&mut self.s, ";")?; } self.end()?; self.end() // close the outer-box } else { self.print_where_clause(&generics.where_clause)?; self.nbsp()?; self.bopen()?; self.hardbreak_if_not_bol()?; for field in struct_def.fields() { self.hardbreak_if_not_bol()?; self.maybe_print_comment(field.span.lo)?; self.print_outer_attributes(&field.attrs)?; self.print_visibility(&field.vis)?; self.print_name(field.name)?; self.word_nbsp(":")?; self.print_type(&field.ty)?; word(&mut self.s, ",")?; } self.bclose(span) } } pub fn print_variant(&mut self, v: &hir::Variant) -> io::Result<()> { self.head("")?; let generics = hir::Generics::empty(); self.print_struct(&v.node.data, &generics, v.node.name, v.span, false)?; if let Some(d) = v.node.disr_expr { space(&mut self.s)?; self.word_space("=")?; self.ann.nested(self, Nested::Body(d))?; } Ok(()) } pub fn print_method_sig(&mut self, name: ast::Name, m: &hir::MethodSig, vis: &hir::Visibility, arg_names: &[Spanned], body_id: Option) -> io::Result<()> { self.print_fn(&m.decl, m.unsafety, m.constness, m.abi, Some(name), &m.generics, vis, arg_names, body_id) } pub fn print_trait_item(&mut self, ti: &hir::TraitItem) -> io::Result<()> { self.ann.pre(self, NodeSubItem(ti.id))?; self.hardbreak_if_not_bol()?; self.maybe_print_comment(ti.span.lo)?; self.print_outer_attributes(&ti.attrs)?; match ti.node { hir::TraitItemKind::Const(ref ty, default) => { self.print_associated_const(ti.name, &ty, default, &hir::Inherited)?; } hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Required(ref arg_names)) => { self.print_method_sig(ti.name, sig, &hir::Inherited, arg_names, None)?; word(&mut self.s, ";")?; } hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Provided(body)) => { self.head("")?; self.print_method_sig(ti.name, sig, &hir::Inherited, &[], Some(body))?; self.nbsp()?; self.end()?; // need to close a box self.end()?; // need to close a box self.ann.nested(self, Nested::Body(body))?; } hir::TraitItemKind::Type(ref bounds, ref default) => { self.print_associated_type(ti.name, Some(bounds), default.as_ref().map(|ty| &**ty))?; } } self.ann.post(self, NodeSubItem(ti.id)) } pub fn print_impl_item(&mut self, ii: &hir::ImplItem) -> io::Result<()> { self.ann.pre(self, NodeSubItem(ii.id))?; self.hardbreak_if_not_bol()?; self.maybe_print_comment(ii.span.lo)?; self.print_outer_attributes(&ii.attrs)?; match ii.defaultness { hir::Defaultness::Default { .. } => self.word_nbsp("default")?, hir::Defaultness::Final => (), } match ii.node { hir::ImplItemKind::Const(ref ty, expr) => { self.print_associated_const(ii.name, &ty, Some(expr), &ii.vis)?; } hir::ImplItemKind::Method(ref sig, body) => { self.head("")?; self.print_method_sig(ii.name, sig, &ii.vis, &[], Some(body))?; self.nbsp()?; self.end()?; // need to close a box self.end()?; // need to close a box self.ann.nested(self, Nested::Body(body))?; } hir::ImplItemKind::Type(ref ty) => { self.print_associated_type(ii.name, None, Some(ty))?; } } self.ann.post(self, NodeSubItem(ii.id)) } pub fn print_stmt(&mut self, st: &hir::Stmt) -> io::Result<()> { self.maybe_print_comment(st.span.lo)?; match st.node { hir::StmtDecl(ref decl, _) => { self.print_decl(&decl)?; } hir::StmtExpr(ref expr, _) => { self.space_if_not_bol()?; self.print_expr(&expr)?; } hir::StmtSemi(ref expr, _) => { self.space_if_not_bol()?; self.print_expr(&expr)?; word(&mut self.s, ";")?; } } if stmt_ends_with_semi(&st.node) { word(&mut self.s, ";")?; } self.maybe_print_trailing_comment(st.span, None) } pub fn print_block(&mut self, blk: &hir::Block) -> io::Result<()> { self.print_block_with_attrs(blk, &[]) } pub fn print_block_unclosed(&mut self, blk: &hir::Block) -> io::Result<()> { self.print_block_unclosed_indent(blk, indent_unit) } pub fn print_block_unclosed_indent(&mut self, blk: &hir::Block, indented: usize) -> io::Result<()> { self.print_block_maybe_unclosed(blk, indented, &[], false) } pub fn print_block_with_attrs(&mut self, blk: &hir::Block, attrs: &[ast::Attribute]) -> io::Result<()> { self.print_block_maybe_unclosed(blk, indent_unit, attrs, true) } pub fn print_block_maybe_unclosed(&mut self, blk: &hir::Block, indented: usize, attrs: &[ast::Attribute], close_box: bool) -> io::Result<()> { match blk.rules { hir::UnsafeBlock(..) => self.word_space("unsafe")?, hir::PushUnsafeBlock(..) => self.word_space("push_unsafe")?, hir::PopUnsafeBlock(..) => self.word_space("pop_unsafe")?, hir::DefaultBlock => (), } self.maybe_print_comment(blk.span.lo)?; self.ann.pre(self, NodeBlock(blk))?; self.bopen()?; self.print_inner_attributes(attrs)?; for st in &blk.stmts { self.print_stmt(st)?; } match blk.expr { Some(ref expr) => { self.space_if_not_bol()?; self.print_expr(&expr)?; self.maybe_print_trailing_comment(expr.span, Some(blk.span.hi))?; } _ => (), } self.bclose_maybe_open(blk.span, indented, close_box)?; self.ann.post(self, NodeBlock(blk)) } fn print_else(&mut self, els: Option<&hir::Expr>) -> io::Result<()> { match els { Some(_else) => { match _else.node { // "another else-if" hir::ExprIf(ref i, ref then, ref e) => { self.cbox(indent_unit - 1)?; self.ibox(0)?; word(&mut self.s, " else if ")?; self.print_expr(&i)?; space(&mut self.s)?; self.print_block(&then)?; self.print_else(e.as_ref().map(|e| &**e)) } // "final else" hir::ExprBlock(ref b) => { self.cbox(indent_unit - 1)?; self.ibox(0)?; word(&mut self.s, " else ")?; self.print_block(&b) } // BLEAH, constraints would be great here _ => { panic!("print_if saw if with weird alternative"); } } } _ => Ok(()), } } pub fn print_if(&mut self, test: &hir::Expr, blk: &hir::Block, elseopt: Option<&hir::Expr>) -> io::Result<()> { self.head("if")?; self.print_expr(test)?; space(&mut self.s)?; self.print_block(blk)?; self.print_else(elseopt) } pub fn print_if_let(&mut self, pat: &hir::Pat, expr: &hir::Expr, blk: &hir::Block, elseopt: Option<&hir::Expr>) -> io::Result<()> { self.head("if let")?; self.print_pat(pat)?; space(&mut self.s)?; self.word_space("=")?; self.print_expr(expr)?; space(&mut self.s)?; self.print_block(blk)?; self.print_else(elseopt) } fn print_call_post(&mut self, args: &[hir::Expr]) -> io::Result<()> { self.popen()?; self.commasep_exprs(Inconsistent, args)?; self.pclose() } pub fn print_expr_maybe_paren(&mut self, expr: &hir::Expr) -> io::Result<()> { let needs_par = needs_parentheses(expr); if needs_par { self.popen()?; } self.print_expr(expr)?; if needs_par { self.pclose()?; } Ok(()) } fn print_expr_vec(&mut self, exprs: &[hir::Expr]) -> io::Result<()> { self.ibox(indent_unit)?; word(&mut self.s, "[")?; self.commasep_exprs(Inconsistent, exprs)?; word(&mut self.s, "]")?; self.end() } fn print_expr_repeat(&mut self, element: &hir::Expr, count: hir::BodyId) -> io::Result<()> { self.ibox(indent_unit)?; word(&mut self.s, "[")?; self.print_expr(element)?; self.word_space(";")?; self.ann.nested(self, Nested::Body(count))?; word(&mut self.s, "]")?; self.end() } fn print_expr_struct(&mut self, qpath: &hir::QPath, fields: &[hir::Field], wth: &Option>) -> io::Result<()> { self.print_qpath(qpath, true)?; word(&mut self.s, "{")?; self.commasep_cmnt(Consistent, &fields[..], |s, field| { s.ibox(indent_unit)?; if !field.is_shorthand { s.print_name(field.name.node)?; s.word_space(":")?; } s.print_expr(&field.expr)?; s.end() }, |f| f.span)?; match *wth { Some(ref expr) => { self.ibox(indent_unit)?; if !fields.is_empty() { word(&mut self.s, ",")?; space(&mut self.s)?; } word(&mut self.s, "..")?; self.print_expr(&expr)?; self.end()?; } _ => if !fields.is_empty() { word(&mut self.s, ",")? }, } word(&mut self.s, "}")?; Ok(()) } fn print_expr_tup(&mut self, exprs: &[hir::Expr]) -> io::Result<()> { self.popen()?; self.commasep_exprs(Inconsistent, exprs)?; if exprs.len() == 1 { word(&mut self.s, ",")?; } self.pclose() } fn print_expr_call(&mut self, func: &hir::Expr, args: &[hir::Expr]) -> io::Result<()> { self.print_expr_maybe_paren(func)?; self.print_call_post(args) } fn print_expr_method_call(&mut self, name: Spanned, tys: &[P], args: &[hir::Expr]) -> io::Result<()> { let base_args = &args[1..]; self.print_expr(&args[0])?; word(&mut self.s, ".")?; self.print_name(name.node)?; if !tys.is_empty() { word(&mut self.s, "::<")?; self.commasep(Inconsistent, tys, |s, ty| s.print_type(&ty))?; word(&mut self.s, ">")?; } self.print_call_post(base_args) } fn print_expr_binary(&mut self, op: hir::BinOp, lhs: &hir::Expr, rhs: &hir::Expr) -> io::Result<()> { self.print_expr(lhs)?; space(&mut self.s)?; self.word_space(op.node.as_str())?; self.print_expr(rhs) } fn print_expr_unary(&mut self, op: hir::UnOp, expr: &hir::Expr) -> io::Result<()> { word(&mut self.s, op.as_str())?; self.print_expr_maybe_paren(expr) } fn print_expr_addr_of(&mut self, mutability: hir::Mutability, expr: &hir::Expr) -> io::Result<()> { word(&mut self.s, "&")?; self.print_mutability(mutability)?; self.print_expr_maybe_paren(expr) } pub fn print_expr(&mut self, expr: &hir::Expr) -> io::Result<()> { self.maybe_print_comment(expr.span.lo)?; self.print_outer_attributes(&expr.attrs)?; self.ibox(indent_unit)?; self.ann.pre(self, NodeExpr(expr))?; match expr.node { hir::ExprBox(ref expr) => { self.word_space("box")?; self.print_expr(expr)?; } hir::ExprArray(ref exprs) => { self.print_expr_vec(exprs)?; } hir::ExprRepeat(ref element, count) => { self.print_expr_repeat(&element, count)?; } hir::ExprStruct(ref qpath, ref fields, ref wth) => { self.print_expr_struct(qpath, &fields[..], wth)?; } hir::ExprTup(ref exprs) => { self.print_expr_tup(exprs)?; } hir::ExprCall(ref func, ref args) => { self.print_expr_call(&func, args)?; } hir::ExprMethodCall(name, ref tys, ref args) => { self.print_expr_method_call(name, &tys[..], args)?; } hir::ExprBinary(op, ref lhs, ref rhs) => { self.print_expr_binary(op, &lhs, &rhs)?; } hir::ExprUnary(op, ref expr) => { self.print_expr_unary(op, &expr)?; } hir::ExprAddrOf(m, ref expr) => { self.print_expr_addr_of(m, &expr)?; } hir::ExprLit(ref lit) => { self.print_literal(&lit)?; } hir::ExprCast(ref expr, ref ty) => { self.print_expr(&expr)?; space(&mut self.s)?; self.word_space("as")?; self.print_type(&ty)?; } hir::ExprType(ref expr, ref ty) => { self.print_expr(&expr)?; self.word_space(":")?; self.print_type(&ty)?; } hir::ExprIf(ref test, ref blk, ref elseopt) => { self.print_if(&test, &blk, elseopt.as_ref().map(|e| &**e))?; } hir::ExprWhile(ref test, ref blk, opt_sp_name) => { if let Some(sp_name) = opt_sp_name { self.print_name(sp_name.node)?; self.word_space(":")?; } self.head("while")?; self.print_expr(&test)?; space(&mut self.s)?; self.print_block(&blk)?; } hir::ExprLoop(ref blk, opt_sp_name, _) => { if let Some(sp_name) = opt_sp_name { self.print_name(sp_name.node)?; self.word_space(":")?; } self.head("loop")?; space(&mut self.s)?; self.print_block(&blk)?; } hir::ExprMatch(ref expr, ref arms, _) => { self.cbox(indent_unit)?; self.ibox(4)?; self.word_nbsp("match")?; self.print_expr(&expr)?; space(&mut self.s)?; self.bopen()?; for arm in arms { self.print_arm(arm)?; } self.bclose_(expr.span, indent_unit)?; } hir::ExprClosure(capture_clause, ref decl, body, _fn_decl_span) => { self.print_capture_clause(capture_clause)?; self.print_closure_args(&decl, body)?; space(&mut self.s)?; // this is a bare expression self.ann.nested(self, Nested::Body(body))?; self.end()?; // need to close a box // a box will be closed by print_expr, but we didn't want an overall // wrapper so we closed the corresponding opening. so create an // empty box to satisfy the close. self.ibox(0)?; } hir::ExprBlock(ref blk) => { // containing cbox, will be closed by print-block at } self.cbox(indent_unit)?; // head-box, will be closed by print-block after { self.ibox(0)?; self.print_block(&blk)?; } hir::ExprAssign(ref lhs, ref rhs) => { self.print_expr(&lhs)?; space(&mut self.s)?; self.word_space("=")?; self.print_expr(&rhs)?; } hir::ExprAssignOp(op, ref lhs, ref rhs) => { self.print_expr(&lhs)?; space(&mut self.s)?; word(&mut self.s, op.node.as_str())?; self.word_space("=")?; self.print_expr(&rhs)?; } hir::ExprField(ref expr, name) => { self.print_expr(&expr)?; word(&mut self.s, ".")?; self.print_name(name.node)?; } hir::ExprTupField(ref expr, id) => { self.print_expr(&expr)?; word(&mut self.s, ".")?; self.print_usize(id.node)?; } hir::ExprIndex(ref expr, ref index) => { self.print_expr(&expr)?; word(&mut self.s, "[")?; self.print_expr(&index)?; word(&mut self.s, "]")?; } hir::ExprPath(ref qpath) => { self.print_qpath(qpath, true)? } hir::ExprBreak(opt_label, ref opt_expr) => { word(&mut self.s, "break")?; space(&mut self.s)?; if let Some(label) = opt_label { self.print_name(label.name)?; space(&mut self.s)?; } if let Some(ref expr) = *opt_expr { self.print_expr(expr)?; space(&mut self.s)?; } } hir::ExprAgain(opt_label) => { word(&mut self.s, "continue")?; space(&mut self.s)?; if let Some(label) = opt_label { self.print_name(label.name)?; space(&mut self.s)? } } hir::ExprRet(ref result) => { word(&mut self.s, "return")?; match *result { Some(ref expr) => { word(&mut self.s, " ")?; self.print_expr(&expr)?; } _ => (), } } hir::ExprInlineAsm(ref a, ref outputs, ref inputs) => { word(&mut self.s, "asm!")?; self.popen()?; self.print_string(&a.asm.as_str(), a.asm_str_style)?; self.word_space(":")?; let mut out_idx = 0; self.commasep(Inconsistent, &a.outputs, |s, out| { let constraint = out.constraint.as_str(); let mut ch = constraint.chars(); match ch.next() { Some('=') if out.is_rw => { s.print_string(&format!("+{}", ch.as_str()), ast::StrStyle::Cooked)? } _ => s.print_string(&constraint, ast::StrStyle::Cooked)?, } s.popen()?; s.print_expr(&outputs[out_idx])?; s.pclose()?; out_idx += 1; Ok(()) })?; space(&mut self.s)?; self.word_space(":")?; let mut in_idx = 0; self.commasep(Inconsistent, &a.inputs, |s, co| { s.print_string(&co.as_str(), ast::StrStyle::Cooked)?; s.popen()?; s.print_expr(&inputs[in_idx])?; s.pclose()?; in_idx += 1; Ok(()) })?; space(&mut self.s)?; self.word_space(":")?; self.commasep(Inconsistent, &a.clobbers, |s, co| { s.print_string(&co.as_str(), ast::StrStyle::Cooked)?; Ok(()) })?; let mut options = vec![]; if a.volatile { options.push("volatile"); } if a.alignstack { options.push("alignstack"); } if a.dialect == ast::AsmDialect::Intel { options.push("intel"); } if !options.is_empty() { space(&mut self.s)?; self.word_space(":")?; self.commasep(Inconsistent, &options, |s, &co| { s.print_string(co, ast::StrStyle::Cooked)?; Ok(()) })?; } self.pclose()?; } } self.ann.post(self, NodeExpr(expr))?; self.end() } pub fn print_local_decl(&mut self, loc: &hir::Local) -> io::Result<()> { self.print_pat(&loc.pat)?; if let Some(ref ty) = loc.ty { self.word_space(":")?; self.print_type(&ty)?; } Ok(()) } pub fn print_decl(&mut self, decl: &hir::Decl) -> io::Result<()> { self.maybe_print_comment(decl.span.lo)?; match decl.node { hir::DeclLocal(ref loc) => { self.space_if_not_bol()?; self.ibox(indent_unit)?; self.word_nbsp("let")?; self.ibox(indent_unit)?; self.print_local_decl(&loc)?; self.end()?; if let Some(ref init) = loc.init { self.nbsp()?; self.word_space("=")?; self.print_expr(&init)?; } self.end() } hir::DeclItem(item) => { self.ann.nested(self, Nested::Item(item)) } } } pub fn print_usize(&mut self, i: usize) -> io::Result<()> { word(&mut self.s, &i.to_string()) } pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> { word(&mut self.s, &name.as_str())?; self.ann.post(self, NodeName(&name)) } pub fn print_for_decl(&mut self, loc: &hir::Local, coll: &hir::Expr) -> io::Result<()> { self.print_local_decl(loc)?; space(&mut self.s)?; self.word_space("in")?; self.print_expr(coll) } pub fn print_path(&mut self, path: &hir::Path, colons_before_params: bool) -> io::Result<()> { self.maybe_print_comment(path.span.lo)?; for (i, segment) in path.segments.iter().enumerate() { if i > 0 { word(&mut self.s, "::")? } if segment.name != keywords::CrateRoot.name() && segment.name != "$crate" { self.print_name(segment.name)?; self.print_path_parameters(&segment.parameters, colons_before_params)?; } } Ok(()) } pub fn print_qpath(&mut self, qpath: &hir::QPath, colons_before_params: bool) -> io::Result<()> { match *qpath { hir::QPath::Resolved(None, ref path) => { self.print_path(path, colons_before_params) } hir::QPath::Resolved(Some(ref qself), ref path) => { word(&mut self.s, "<")?; self.print_type(qself)?; space(&mut self.s)?; self.word_space("as")?; for (i, segment) in path.segments[..path.segments.len() - 1].iter().enumerate() { if i > 0 { word(&mut self.s, "::")? } if segment.name != keywords::CrateRoot.name() && segment.name != "$crate" { self.print_name(segment.name)?; self.print_path_parameters(&segment.parameters, colons_before_params)?; } } word(&mut self.s, ">")?; word(&mut self.s, "::")?; let item_segment = path.segments.last().unwrap(); self.print_name(item_segment.name)?; self.print_path_parameters(&item_segment.parameters, colons_before_params) } hir::QPath::TypeRelative(ref qself, ref item_segment) => { word(&mut self.s, "<")?; self.print_type(qself)?; word(&mut self.s, ">")?; word(&mut self.s, "::")?; self.print_name(item_segment.name)?; self.print_path_parameters(&item_segment.parameters, colons_before_params) } } } fn print_path_parameters(&mut self, parameters: &hir::PathParameters, colons_before_params: bool) -> io::Result<()> { match *parameters { hir::AngleBracketedParameters(ref data) => { let start = if colons_before_params { "::<" } else { "<" }; let empty = Cell::new(true); let start_or_comma = |this: &mut Self| { if empty.get() { empty.set(false); word(&mut this.s, start) } else { this.word_space(",") } }; if !data.lifetimes.iter().all(|lt| lt.is_elided()) { for lifetime in &data.lifetimes { start_or_comma(self)?; self.print_lifetime(lifetime)?; } } if !data.types.is_empty() { start_or_comma(self)?; self.commasep(Inconsistent, &data.types, |s, ty| s.print_type(&ty))?; } // FIXME(eddyb) This would leak into error messages, e.g.: // "non-exhaustive patterns: `Some::<..>(_)` not covered". if data.infer_types && false { start_or_comma(self)?; word(&mut self.s, "..")?; } for binding in data.bindings.iter() { start_or_comma(self)?; self.print_name(binding.name)?; space(&mut self.s)?; self.word_space("=")?; self.print_type(&binding.ty)?; } if !empty.get() { word(&mut self.s, ">")? } } hir::ParenthesizedParameters(ref data) => { word(&mut self.s, "(")?; self.commasep(Inconsistent, &data.inputs, |s, ty| s.print_type(&ty))?; word(&mut self.s, ")")?; if let Some(ref ty) = data.output { self.space_if_not_bol()?; self.word_space("->")?; self.print_type(&ty)?; } } } Ok(()) } pub fn print_pat(&mut self, pat: &hir::Pat) -> io::Result<()> { self.maybe_print_comment(pat.span.lo)?; self.ann.pre(self, NodePat(pat))?; // Pat isn't normalized, but the beauty of it // is that it doesn't matter match pat.node { PatKind::Wild => word(&mut self.s, "_")?, PatKind::Binding(binding_mode, _, ref path1, ref sub) => { match binding_mode { hir::BindByRef(mutbl) => { self.word_nbsp("ref")?; self.print_mutability(mutbl)?; } hir::BindByValue(hir::MutImmutable) => {} hir::BindByValue(hir::MutMutable) => { self.word_nbsp("mut")?; } } self.print_name(path1.node)?; if let Some(ref p) = *sub { word(&mut self.s, "@")?; self.print_pat(&p)?; } } PatKind::TupleStruct(ref qpath, ref elts, ddpos) => { self.print_qpath(qpath, true)?; self.popen()?; if let Some(ddpos) = ddpos { self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(&p))?; if ddpos != 0 { self.word_space(",")?; } word(&mut self.s, "..")?; if ddpos != elts.len() { word(&mut self.s, ",")?; self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(&p))?; } } else { self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(&p))?; } self.pclose()?; } PatKind::Path(ref qpath) => { self.print_qpath(qpath, true)?; } PatKind::Struct(ref qpath, ref fields, etc) => { self.print_qpath(qpath, true)?; self.nbsp()?; self.word_space("{")?; self.commasep_cmnt(Consistent, &fields[..], |s, f| { s.cbox(indent_unit)?; if !f.node.is_shorthand { s.print_name(f.node.name)?; s.word_nbsp(":")?; } s.print_pat(&f.node.pat)?; s.end() }, |f| f.node.pat.span)?; if etc { if !fields.is_empty() { self.word_space(",")?; } word(&mut self.s, "..")?; } space(&mut self.s)?; word(&mut self.s, "}")?; } PatKind::Tuple(ref elts, ddpos) => { self.popen()?; if let Some(ddpos) = ddpos { self.commasep(Inconsistent, &elts[..ddpos], |s, p| s.print_pat(&p))?; if ddpos != 0 { self.word_space(",")?; } word(&mut self.s, "..")?; if ddpos != elts.len() { word(&mut self.s, ",")?; self.commasep(Inconsistent, &elts[ddpos..], |s, p| s.print_pat(&p))?; } } else { self.commasep(Inconsistent, &elts[..], |s, p| s.print_pat(&p))?; if elts.len() == 1 { word(&mut self.s, ",")?; } } self.pclose()?; } PatKind::Box(ref inner) => { word(&mut self.s, "box ")?; self.print_pat(&inner)?; } PatKind::Ref(ref inner, mutbl) => { word(&mut self.s, "&")?; if mutbl == hir::MutMutable { word(&mut self.s, "mut ")?; } self.print_pat(&inner)?; } PatKind::Lit(ref e) => self.print_expr(&e)?, PatKind::Range(ref begin, ref end, ref end_kind) => { self.print_expr(&begin)?; space(&mut self.s)?; match *end_kind { RangeEnd::Included => word(&mut self.s, "...")?, RangeEnd::Excluded => word(&mut self.s, "..")?, } self.print_expr(&end)?; } PatKind::Slice(ref before, ref slice, ref after) => { word(&mut self.s, "[")?; self.commasep(Inconsistent, &before[..], |s, p| s.print_pat(&p))?; if let Some(ref p) = *slice { if !before.is_empty() { self.word_space(",")?; } if p.node != PatKind::Wild { self.print_pat(&p)?; } word(&mut self.s, "..")?; if !after.is_empty() { self.word_space(",")?; } } self.commasep(Inconsistent, &after[..], |s, p| s.print_pat(&p))?; word(&mut self.s, "]")?; } } self.ann.post(self, NodePat(pat)) } fn print_arm(&mut self, arm: &hir::Arm) -> io::Result<()> { // I have no idea why this check is necessary, but here it // is :( if arm.attrs.is_empty() { space(&mut self.s)?; } self.cbox(indent_unit)?; self.ibox(0)?; self.print_outer_attributes(&arm.attrs)?; let mut first = true; for p in &arm.pats { if first { first = false; } else { space(&mut self.s)?; self.word_space("|")?; } self.print_pat(&p)?; } space(&mut self.s)?; if let Some(ref e) = arm.guard { self.word_space("if")?; self.print_expr(&e)?; space(&mut self.s)?; } self.word_space("=>")?; match arm.body.node { hir::ExprBlock(ref blk) => { // the block will close the pattern's ibox self.print_block_unclosed_indent(&blk, indent_unit)?; // If it is a user-provided unsafe block, print a comma after it if let hir::UnsafeBlock(hir::UserProvided) = blk.rules { word(&mut self.s, ",")?; } } _ => { self.end()?; // close the ibox for the pattern self.print_expr(&arm.body)?; word(&mut self.s, ",")?; } } self.end() // close enclosing cbox } pub fn print_fn(&mut self, decl: &hir::FnDecl, unsafety: hir::Unsafety, constness: hir::Constness, abi: Abi, name: Option, generics: &hir::Generics, vis: &hir::Visibility, arg_names: &[Spanned], body_id: Option) -> io::Result<()> { self.print_fn_header_info(unsafety, constness, abi, vis)?; if let Some(name) = name { self.nbsp()?; self.print_name(name)?; } self.print_generics(generics)?; self.popen()?; let mut i = 0; // Make sure we aren't supplied *both* `arg_names` and `body_id`. assert!(arg_names.is_empty() || body_id.is_none()); self.commasep(Inconsistent, &decl.inputs, |s, ty| { s.ibox(indent_unit)?; if let Some(name) = arg_names.get(i) { word(&mut s.s, &name.node.as_str())?; word(&mut s.s, ":")?; space(&mut s.s)?; } else if let Some(body_id) = body_id { s.ann.nested(s, Nested::BodyArgPat(body_id, i))?; word(&mut s.s, ":")?; space(&mut s.s)?; } i += 1; s.print_type(ty)?; s.end() })?; if decl.variadic { word(&mut self.s, ", ...")?; } self.pclose()?; self.print_fn_output(decl)?; self.print_where_clause(&generics.where_clause) } fn print_closure_args(&mut self, decl: &hir::FnDecl, body_id: hir::BodyId) -> io::Result<()> { word(&mut self.s, "|")?; let mut i = 0; self.commasep(Inconsistent, &decl.inputs, |s, ty| { s.ibox(indent_unit)?; s.ann.nested(s, Nested::BodyArgPat(body_id, i))?; i += 1; if ty.node != hir::TyInfer { word(&mut s.s, ":")?; space(&mut s.s)?; s.print_type(ty)?; } s.end() })?; word(&mut self.s, "|")?; if let hir::DefaultReturn(..) = decl.output { return Ok(()); } self.space_if_not_bol()?; self.word_space("->")?; match decl.output { hir::Return(ref ty) => { self.print_type(&ty)?; self.maybe_print_comment(ty.span.lo) } hir::DefaultReturn(..) => unreachable!(), } } pub fn print_capture_clause(&mut self, capture_clause: hir::CaptureClause) -> io::Result<()> { match capture_clause { hir::CaptureByValue => self.word_space("move"), hir::CaptureByRef => Ok(()), } } pub fn print_bounds(&mut self, prefix: &str, bounds: &[hir::TyParamBound]) -> io::Result<()> { if !bounds.is_empty() { word(&mut self.s, prefix)?; let mut first = true; for bound in bounds { self.nbsp()?; if first { first = false; } else { self.word_space("+")?; } match *bound { TraitTyParamBound(ref tref, TraitBoundModifier::None) => { self.print_poly_trait_ref(tref) } TraitTyParamBound(ref tref, TraitBoundModifier::Maybe) => { word(&mut self.s, "?")?; self.print_poly_trait_ref(tref) } RegionTyParamBound(ref lt) => { self.print_lifetime(lt) } }? } Ok(()) } else { Ok(()) } } pub fn print_lifetime(&mut self, lifetime: &hir::Lifetime) -> io::Result<()> { self.print_name(lifetime.name) } pub fn print_lifetime_def(&mut self, lifetime: &hir::LifetimeDef) -> io::Result<()> { self.print_lifetime(&lifetime.lifetime)?; let mut sep = ":"; for v in &lifetime.bounds { word(&mut self.s, sep)?; self.print_lifetime(v)?; sep = "+"; } Ok(()) } pub fn print_generics(&mut self, generics: &hir::Generics) -> io::Result<()> { let total = generics.lifetimes.len() + generics.ty_params.len(); if total == 0 { return Ok(()); } word(&mut self.s, "<")?; let mut ints = Vec::new(); for i in 0..total { ints.push(i); } self.commasep(Inconsistent, &ints[..], |s, &idx| { if idx < generics.lifetimes.len() { let lifetime = &generics.lifetimes[idx]; s.print_lifetime_def(lifetime) } else { let idx = idx - generics.lifetimes.len(); let param = &generics.ty_params[idx]; s.print_ty_param(param) } })?; word(&mut self.s, ">")?; Ok(()) } pub fn print_ty_param(&mut self, param: &hir::TyParam) -> io::Result<()> { self.print_name(param.name)?; self.print_bounds(":", ¶m.bounds)?; match param.default { Some(ref default) => { space(&mut self.s)?; self.word_space("=")?; self.print_type(&default) } _ => Ok(()), } } pub fn print_where_clause(&mut self, where_clause: &hir::WhereClause) -> io::Result<()> { if where_clause.predicates.is_empty() { return Ok(()); } space(&mut self.s)?; self.word_space("where")?; for (i, predicate) in where_clause.predicates.iter().enumerate() { if i != 0 { self.word_space(",")?; } match predicate { &hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate{ref bound_lifetimes, ref bounded_ty, ref bounds, ..}) => { self.print_formal_lifetime_list(bound_lifetimes)?; self.print_type(&bounded_ty)?; self.print_bounds(":", bounds)?; } &hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate{ref lifetime, ref bounds, ..}) => { self.print_lifetime(lifetime)?; word(&mut self.s, ":")?; for (i, bound) in bounds.iter().enumerate() { self.print_lifetime(bound)?; if i != 0 { word(&mut self.s, ":")?; } } } &hir::WherePredicate::EqPredicate(hir::WhereEqPredicate{ref lhs_ty, ref rhs_ty, ..}) => { self.print_type(lhs_ty)?; space(&mut self.s)?; self.word_space("=")?; self.print_type(rhs_ty)?; } } } Ok(()) } pub fn print_mutability(&mut self, mutbl: hir::Mutability) -> io::Result<()> { match mutbl { hir::MutMutable => self.word_nbsp("mut"), hir::MutImmutable => Ok(()), } } pub fn print_mt(&mut self, mt: &hir::MutTy) -> io::Result<()> { self.print_mutability(mt.mutbl)?; self.print_type(&mt.ty) } pub fn print_fn_output(&mut self, decl: &hir::FnDecl) -> io::Result<()> { if let hir::DefaultReturn(..) = decl.output { return Ok(()); } self.space_if_not_bol()?; self.ibox(indent_unit)?; self.word_space("->")?; match decl.output { hir::DefaultReturn(..) => unreachable!(), hir::Return(ref ty) => self.print_type(&ty)?, } self.end()?; match decl.output { hir::Return(ref output) => self.maybe_print_comment(output.span.lo), _ => Ok(()), } } pub fn print_ty_fn(&mut self, abi: Abi, unsafety: hir::Unsafety, decl: &hir::FnDecl, name: Option, generics: &hir::Generics) -> io::Result<()> { self.ibox(indent_unit)?; if !generics.lifetimes.is_empty() || !generics.ty_params.is_empty() { word(&mut self.s, "for")?; self.print_generics(generics)?; } let generics = hir::Generics { lifetimes: hir::HirVec::new(), ty_params: hir::HirVec::new(), where_clause: hir::WhereClause { id: ast::DUMMY_NODE_ID, predicates: hir::HirVec::new(), }, span: syntax_pos::DUMMY_SP, }; self.print_fn(decl, unsafety, hir::Constness::NotConst, abi, name, &generics, &hir::Inherited, &[], None)?; self.end() } pub fn maybe_print_trailing_comment(&mut self, span: syntax_pos::Span, next_pos: Option) -> io::Result<()> { let cm = match self.cm { Some(cm) => cm, _ => return Ok(()), }; if let Some(ref cmnt) = self.next_comment() { if (*cmnt).style != comments::Trailing { return Ok(()); } let span_line = cm.lookup_char_pos(span.hi); let comment_line = cm.lookup_char_pos((*cmnt).pos); let mut next = (*cmnt).pos + BytePos(1); if let Some(p) = next_pos { next = p; } if span.hi < (*cmnt).pos && (*cmnt).pos < next && span_line.line == comment_line.line { self.print_comment(cmnt)?; self.cur_cmnt_and_lit.cur_cmnt += 1; } } Ok(()) } pub fn print_remaining_comments(&mut self) -> io::Result<()> { // If there aren't any remaining comments, then we need to manually // make sure there is a line break at the end. if self.next_comment().is_none() { hardbreak(&mut self.s)?; } loop { match self.next_comment() { Some(ref cmnt) => { self.print_comment(cmnt)?; self.cur_cmnt_and_lit.cur_cmnt += 1; } _ => break, } } Ok(()) } pub fn print_opt_abi_and_extern_if_nondefault(&mut self, opt_abi: Option) -> io::Result<()> { match opt_abi { Some(Abi::Rust) => Ok(()), Some(abi) => { self.word_nbsp("extern")?; self.word_nbsp(&abi.to_string()) } None => Ok(()), } } pub fn print_extern_opt_abi(&mut self, opt_abi: Option) -> io::Result<()> { match opt_abi { Some(abi) => { self.word_nbsp("extern")?; self.word_nbsp(&abi.to_string()) } None => Ok(()), } } pub fn print_fn_header_info(&mut self, unsafety: hir::Unsafety, constness: hir::Constness, abi: Abi, vis: &hir::Visibility) -> io::Result<()> { word(&mut self.s, &visibility_qualified(vis, ""))?; self.print_unsafety(unsafety)?; match constness { hir::Constness::NotConst => {} hir::Constness::Const => self.word_nbsp("const")?, } if abi != Abi::Rust { self.word_nbsp("extern")?; self.word_nbsp(&abi.to_string())?; } word(&mut self.s, "fn") } pub fn print_unsafety(&mut self, s: hir::Unsafety) -> io::Result<()> { match s { hir::Unsafety::Normal => Ok(()), hir::Unsafety::Unsafe => self.word_nbsp("unsafe"), } } } // Dup'ed from parse::classify, but adapted for the HIR. /// Does this expression require a semicolon to be treated /// as a statement? The negation of this: 'can this expression /// be used as a statement without a semicolon' -- is used /// as an early-bail-out in the parser so that, for instance, /// if true {...} else {...} /// |x| 5 /// isn't parsed as (if true {...} else {...} | x) | 5 fn expr_requires_semi_to_be_stmt(e: &hir::Expr) -> bool { match e.node { hir::ExprIf(..) | hir::ExprMatch(..) | hir::ExprBlock(_) | hir::ExprWhile(..) | hir::ExprLoop(..) => false, _ => true, } } /// this statement requires a semicolon after it. /// note that in one case (stmt_semi), we've already /// seen the semicolon, and thus don't need another. fn stmt_ends_with_semi(stmt: &hir::Stmt_) -> bool { match *stmt { hir::StmtDecl(ref d, _) => { match d.node { hir::DeclLocal(_) => true, hir::DeclItem(_) => false, } } hir::StmtExpr(ref e, _) => { expr_requires_semi_to_be_stmt(&e) } hir::StmtSemi(..) => { false } } }