Auto merge of #21598 - eddyb:there-are-no-boxed-closures, r=brson

3 files changed, 41 insertions, 143 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 25a30b5e8e2..4f6cd8ad356 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -35,7 +35,6 @@ pub use self::MacStmtStyle::*;
 pub use self::MetaItem_::*;
 pub use self::Method_::*;
 pub use self::Mutability::*;
-pub use self::Onceness::*;
 pub use self::Pat_::*;
 pub use self::PathListItem_::*;
 pub use self::PatWildKind::*;
@@ -49,7 +48,7 @@ pub use self::TraitItem::*;
 pub use self::Ty_::*;
 pub use self::TyParamBound::*;
 pub use self::UintTy::*;
-pub use self::UnboxedClosureKind::*;
+pub use self::ClosureKind::*;
 pub use self::UnOp::*;
 pub use self::UnsafeSource::*;
 pub use self::VariantKind::*;
@@ -734,7 +733,7 @@ pub enum Expr_ {
     // FIXME #6993: change to Option<Name> ... or not, if these are hygienic.
     ExprLoop(P<Block>, Option<Ident>),
     ExprMatch(P<Expr>, Vec<Arm>, MatchSource),
-    ExprClosure(CaptureClause, Option<UnboxedClosureKind>, P<FnDecl>, P<Block>),
+    ExprClosure(CaptureClause, Option<ClosureKind>, P<FnDecl>, P<Block>),
     ExprBlock(P<Block>),
 
     ExprAssign(P<Expr>, P<Expr>),
@@ -1222,31 +1221,6 @@ pub enum PrimTy {
     TyChar
 }
 
-#[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Copy, Show)]
-pub enum Onceness {
-    Once,
-    Many
-}
-
-impl fmt::Display for Onceness {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Display::fmt(match *self {
-            Once => "once",
-            Many => "many",
-        }, f)
-    }
-}
-
-/// Represents the type of a closure
-#[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show)]
-pub struct ClosureTy {
-    pub lifetimes: Vec<LifetimeDef>,
-    pub unsafety: Unsafety,
-    pub onceness: Onceness,
-    pub decl: P<FnDecl>,
-    pub bounds: TyParamBounds,
-}
-
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show)]
 pub struct BareFnTy {
     pub unsafety: Unsafety,
@@ -1710,10 +1684,10 @@ impl ForeignItem_ {
 }
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show, Copy)]
-pub enum UnboxedClosureKind {
-    FnUnboxedClosureKind,
-    FnMutUnboxedClosureKind,
-    FnOnceUnboxedClosureKind,
+pub enum ClosureKind {
+    FnClosureKind,
+    FnMutClosureKind,
+    FnOnceClosureKind,
 }
 
 /// The data we save and restore about an inlined item or method.  This is not
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 759e5e8229a..eab24574bb1 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -28,8 +28,8 @@ use ast::{ExprLit, ExprLoop, ExprMac, ExprRange};
 use ast::{ExprMethodCall, ExprParen, ExprPath, ExprQPath};
 use ast::{ExprRepeat, ExprRet, ExprStruct, ExprTup, ExprUnary};
 use ast::{ExprVec, ExprWhile, ExprWhileLet, ExprForLoop, Field, FnDecl};
-use ast::{FnUnboxedClosureKind, FnMutUnboxedClosureKind};
-use ast::{FnOnceUnboxedClosureKind};
+use ast::{FnClosureKind, FnMutClosureKind};
+use ast::{FnOnceClosureKind};
 use ast::{ForeignItem, ForeignItemStatic, ForeignItemFn, ForeignMod, FunctionRetTy};
 use ast::{Ident, Inherited, ImplItem, Item, Item_, ItemStatic};
 use ast::{ItemEnum, ItemFn, ItemForeignMod, ItemImpl, ItemConst};
@@ -57,7 +57,7 @@ use ast::{TyFixedLengthVec, TyBareFn};
 use ast::{TyTypeof, TyInfer, TypeMethod};
 use ast::{TyParam, TyParamBound, TyParen, TyPath, TyPolyTraitRef, TyPtr, TyQPath};
 use ast::{TyRptr, TyTup, TyU32, TyVec, UnUniq};
-use ast::{TypeImplItem, TypeTraitItem, Typedef, UnboxedClosureKind};
+use ast::{TypeImplItem, TypeTraitItem, Typedef, ClosureKind};
 use ast::{UnnamedField, UnsafeBlock};
 use ast::{ViewPath, ViewPathGlob, ViewPathList, ViewPathSimple};
 use ast::{Visibility, WhereClause};
@@ -1133,27 +1133,26 @@ impl<'a> Parser<'a> {
         TyInfer
     }
 
-    /// Parses an optional unboxed closure kind (`&:`, `&mut:`, or `:`).
-    pub fn parse_optional_unboxed_closure_kind(&mut self)
-                                               -> Option<UnboxedClosureKind> {
+    /// Parses an optional closure kind (`&:`, `&mut:`, or `:`).
+    pub fn parse_optional_closure_kind(&mut self) -> Option<ClosureKind> {
         if self.check(&token::BinOp(token::And)) &&
                 self.look_ahead(1, |t| t.is_keyword(keywords::Mut)) &&
                 self.look_ahead(2, |t| *t == token::Colon) {
             self.bump();
             self.bump();
             self.bump();
-            return Some(FnMutUnboxedClosureKind)
+            return Some(FnMutClosureKind)
         }
 
         if self.token == token::BinOp(token::And) &&
                     self.look_ahead(1, |t| *t == token::Colon) {
             self.bump();
             self.bump();
-            return Some(FnUnboxedClosureKind)
+            return Some(FnClosureKind)
         }
 
         if self.eat(&token::Colon) {
-            return Some(FnOnceUnboxedClosureKind)
+            return Some(FnOnceClosureKind)
         }
 
         return None
@@ -3023,8 +3022,7 @@ impl<'a> Parser<'a> {
                              -> P<Expr>
     {
         let lo = self.span.lo;
-        let (decl, optional_unboxed_closure_kind) =
-            self.parse_fn_block_decl();
+        let (decl, optional_closure_kind) = self.parse_fn_block_decl();
         let body = self.parse_expr();
         let fakeblock = P(ast::Block {
             id: ast::DUMMY_NODE_ID,
@@ -3037,7 +3035,7 @@ impl<'a> Parser<'a> {
         self.mk_expr(
             lo,
             fakeblock.span.hi,
-            ExprClosure(capture_clause, optional_unboxed_closure_kind, decl, fakeblock))
+            ExprClosure(capture_clause, optional_closure_kind, decl, fakeblock))
     }
 
     pub fn parse_else_expr(&mut self) -> P<Expr> {
@@ -4506,22 +4504,21 @@ impl<'a> Parser<'a> {
     }
 
     // parse the |arg, arg| header on a lambda
-    fn parse_fn_block_decl(&mut self)
-                           -> (P<FnDecl>, Option<UnboxedClosureKind>) {
-        let (optional_unboxed_closure_kind, inputs_captures) = {
+    fn parse_fn_block_decl(&mut self) -> (P<FnDecl>, Option<ClosureKind>) {
+        let (optional_closure_kind, inputs_captures) = {
             if self.eat(&token::OrOr) {
                 (None, Vec::new())
             } else {
                 self.expect(&token::BinOp(token::Or));
-                let optional_unboxed_closure_kind =
-                    self.parse_optional_unboxed_closure_kind();
+                let optional_closure_kind =
+                    self.parse_optional_closure_kind();
                 let args = self.parse_seq_to_before_end(
                     &token::BinOp(token::Or),
                     seq_sep_trailing_allowed(token::Comma),
                     |p| p.parse_fn_block_arg()
                 );
                 self.bump();
-                (optional_unboxed_closure_kind, args)
+                (optional_closure_kind, args)
             }
         };
         let output = self.parse_ret_ty();
@@ -4530,7 +4527,7 @@ impl<'a> Parser<'a> {
             inputs: inputs_captures,
             output: output,
             variadic: false
-        }), optional_unboxed_closure_kind)
+        }), optional_closure_kind)
     }
 
     /// Parses the `(arg, arg) -> return_type` header on a procedure.
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 699b4f43b14..d06ac50920e 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -11,11 +11,11 @@
 pub use self::AnnNode::*;
 
 use abi;
-use ast::{self, FnUnboxedClosureKind, FnMutUnboxedClosureKind};
-use ast::{FnOnceUnboxedClosureKind};
+use ast::{self, FnClosureKind, FnMutClosureKind};
+use ast::{FnOnceClosureKind};
 use ast::{MethodImplItem, RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
 use ast::{RequiredMethod, ProvidedMethod, TypeImplItem, TypeTraitItem};
-use ast::{UnboxedClosureKind};
+use ast::{ClosureKind};
 use ast_util;
 use owned_slice::OwnedSlice;
 use attr::{AttrMetaMethods, AttributeMethods};
@@ -703,14 +703,11 @@ impl<'a> State<'a> {
                         predicates: Vec::new(),
                     },
                 };
-                try!(self.print_ty_fn(Some(f.abi),
-                                      None,
+                try!(self.print_ty_fn(f.abi,
                                       f.unsafety,
-                                      ast::Many,
                                       &*f.decl,
                                       None,
-                                      &OwnedSlice::empty(),
-                                      Some(&generics),
+                                      &generics,
                                       None));
             }
             ast::TyPath(ref path, _) => {
@@ -1215,14 +1212,11 @@ impl<'a> State<'a> {
         try!(self.hardbreak_if_not_bol());
         try!(self.maybe_print_comment(m.span.lo));
         try!(self.print_outer_attributes(&m.attrs[]));
-        try!(self.print_ty_fn(None,
-                              None,
+        try!(self.print_ty_fn(m.abi,
                               m.unsafety,
-                              ast::Many,
                               &*m.decl,
                               Some(m.ident),
-                              &OwnedSlice::empty(),
-                              Some(&m.generics),
+                              &m.generics,
                               Some(&m.explicit_self.node)));
         word(&mut self.s, ";")
     }
@@ -2300,7 +2294,7 @@ impl<'a> State<'a> {
                     opt_explicit_self: Option<&ast::ExplicitSelf_>,
                     vis: ast::Visibility) -> IoResult<()> {
         try!(self.head(""));
-        try!(self.print_fn_header_info(opt_explicit_self, unsafety, abi, vis));
+        try!(self.print_fn_header_info(unsafety, abi, vis));
         try!(self.nbsp());
         try!(self.print_ident(name));
         try!(self.print_generics(generics));
@@ -2357,14 +2351,14 @@ impl<'a> State<'a> {
     pub fn print_fn_block_args(
             &mut self,
             decl: &ast::FnDecl,
-            unboxed_closure_kind: Option<UnboxedClosureKind>)
+            closure_kind: Option<ClosureKind>)
             -> IoResult<()> {
         try!(word(&mut self.s, "|"));
-        match unboxed_closure_kind {
+        match closure_kind {
             None => {}
-            Some(FnUnboxedClosureKind) => try!(self.word_space("&:")),
-            Some(FnMutUnboxedClosureKind) => try!(self.word_space("&mut:")),
-            Some(FnOnceUnboxedClosureKind) => try!(self.word_space(":")),
+            Some(FnClosureKind) => try!(self.word_space("&:")),
+            Some(FnMutClosureKind) => try!(self.word_space("&mut:")),
+            Some(FnOnceClosureKind) => try!(self.word_space(":")),
         }
         try!(self.print_fn_args(decl, None));
         try!(word(&mut self.s, "|"));
@@ -2396,31 +2390,6 @@ impl<'a> State<'a> {
         }
     }
 
-    pub fn print_proc_args(&mut self, decl: &ast::FnDecl) -> IoResult<()> {
-        try!(word(&mut self.s, "proc"));
-        try!(word(&mut self.s, "("));
-        try!(self.print_fn_args(decl, None));
-        try!(word(&mut self.s, ")"));
-
-        if let ast::DefaultReturn(..) = decl.output {
-            return Ok(());
-        }
-
-        try!(self.space_if_not_bol());
-        try!(self.word_space("->"));
-        match decl.output {
-            ast::Return(ref ty) => {
-                try!(self.print_type(&**ty));
-                self.maybe_print_comment(ty.span.lo)
-            }
-            ast::DefaultReturn(..) => unreachable!(),
-            ast::NoReturn(span) => {
-                try!(self.word_nbsp("!"));
-                self.maybe_print_comment(span.lo)
-            }
-        }
-    }
-
     pub fn print_bounds(&mut self,
                         prefix: &str,
                         bounds: &[ast::TyParamBound])
@@ -2696,31 +2665,15 @@ impl<'a> State<'a> {
     }
 
     pub fn print_ty_fn(&mut self,
-                       opt_abi: Option<abi::Abi>,
-                       opt_sigil: Option<char>,
+                       abi: abi::Abi,
                        unsafety: ast::Unsafety,
-                       onceness: ast::Onceness,
                        decl: &ast::FnDecl,
                        id: Option<ast::Ident>,
-                       bounds: &OwnedSlice<ast::TyParamBound>,
-                       generics: Option<&ast::Generics>,
+                       generics: &ast::Generics,
                        opt_explicit_self: Option<&ast::ExplicitSelf_>)
                        -> IoResult<()> {
         try!(self.ibox(indent_unit));
-
-        // Duplicates the logic in `print_fn_header_info()`.  This is because that
-        // function prints the sigil in the wrong place.  That should be fixed.
-        if opt_sigil == Some('~') && onceness == ast::Once {
-            try!(word(&mut self.s, "proc"));
-        } else if opt_sigil == Some('&') {
-            try!(self.print_unsafety(unsafety));
-            try!(self.print_extern_opt_abi(opt_abi));
-        } else {
-            assert!(opt_sigil.is_none());
-            try!(self.print_unsafety(unsafety));
-            try!(self.print_opt_abi_and_extern_if_nondefault(opt_abi));
-            try!(word(&mut self.s, "fn"));
-        }
+        try!(self.print_fn_header_info(Some(unsafety), abi, ast::Inherited));
 
         match id {
             Some(id) => {
@@ -2730,35 +2683,10 @@ impl<'a> State<'a> {
             _ => ()
         }
 
-        match generics { Some(g) => try!(self.print_generics(g)), _ => () }
+        try!(self.print_generics(generics));
         try!(zerobreak(&mut self.s));
-
-        if opt_sigil == Some('&') {
-            try!(word(&mut self.s, "|"));
-        } else {
-            try!(self.popen());
-        }
-
-        try!(self.print_fn_args(decl, opt_explicit_self));
-
-        if opt_sigil == Some('&') {
-            try!(word(&mut self.s, "|"));
-        } else {
-            if decl.variadic {
-                try!(word(&mut self.s, ", ..."));
-            }
-            try!(self.pclose());
-        }
-
-        try!(self.print_bounds(":", &bounds[]));
-
-        try!(self.print_fn_output(decl));
-
-        match generics {
-            Some(generics) => try!(self.print_where_clause(generics)),
-            None => {}
-        }
-
+        try!(self.print_fn_args_and_ret(decl, opt_explicit_self));
+        try!(self.print_where_clause(generics));
         self.end()
     }
 
@@ -3015,7 +2943,6 @@ impl<'a> State<'a> {
     }
 
     pub fn print_fn_header_info(&mut self,
-                                _opt_explicit_self: Option<&ast::ExplicitSelf_>,
                                 opt_unsafety: Option<ast::Unsafety>,
                                 abi: abi::Abi,
                                 vis: ast::Visibility) -> IoResult<()> {