libsyntax: Introduce routines and remove all @fns from libsyntax save the old visitor

Author: pcwalton

src/libextra/c_vec.rs

@@ -36,22 +36,22 @@
  * still held if needed.
  */
 
-
-use std::option;
+use std::cast;
 use std::ptr;
+use std::routine::Runnable;
+use std::util;
 
 /**
  * The type representing a foreign chunk of memory
- *
  */
 pub struct CVec<T> {
     priv base: *mut T,
     priv len: uint,
-    priv rsrc: @DtorRes
+    priv rsrc: @DtorRes,
 }
 
 struct DtorRes {
-  dtor: Option<@fn()>,
+    dtor: Option<~Runnable>,
 }
 
 #[unsafe_destructor]
@@ -64,9 +64,11 @@ impl Drop for DtorRes {
     }
 }
 
-fn DtorRes(dtor: Option<@fn()>) -> DtorRes {
-    DtorRes {
-        dtor: dtor
+impl DtorRes {
+    fn new(dtor: Option<~Runnable>) -> DtorRes {
+        DtorRes {
+            dtor: dtor,
+        }
     }
 }
 
@@ -83,10 +85,10 @@ fn DtorRes(dtor: Option<@fn()>) -> DtorRes {
  * * len - The number of elements in the buffer
  */
 pub unsafe fn CVec<T>(base: *mut T, len: uint) -> CVec<T> {
-    return CVec{
+    return CVec {
         base: base,
         len: len,
-        rsrc: @DtorRes(option::None)
+        rsrc: @DtorRes::new(None)
     };
 }
 
@@ -101,12 +103,12 @@ pub unsafe fn CVec<T>(base: *mut T, len: uint) -> CVec<T> {
  * * dtor - A function to run when the value is destructed, useful
  *          for freeing the buffer, etc.
  */
-pub unsafe fn c_vec_with_dtor<T>(base: *mut T, len: uint, dtor: @fn())
-  -> CVec<T> {
+pub unsafe fn c_vec_with_dtor<T>(base: *mut T, len: uint, dtor: ~Runnable)
+                                 -> CVec<T> {
     return CVec{
         base: base,
         len: len,
-        rsrc: @DtorRes(option::Some(dtor))
+        rsrc: @DtorRes::new(Some(dtor))
     };
 }
 
@@ -153,6 +155,17 @@ mod tests {
 
     use std::libc::*;
     use std::libc;
+    use std::routine::Runnable;
+
+    struct LibcFree {
+        mem: *c_void,
+    }
+
+    impl Runnable for LibcFree {
+        fn run(~self) {
+            libc::free(self.mem)
+        }
+    }
 
     fn malloc(n: size_t) -> CVec<u8> {
         #[fixed_stack_segment];
@@ -163,12 +176,11 @@ mod tests {
 
             assert!(mem as int != 0);
 
-            return c_vec_with_dtor(mem as *mut u8, n as uint, || f(mem));
-        }
-
-        fn f(mem: *c_void) {
-            #[fixed_stack_segment]; #[inline(never)];
-            unsafe { libc::free(mem) }
+            return c_vec_with_dtor(mem as *mut u8,
+                                   n as uint,
+                                   ~LibcFree {
+                                    mem: mem,
+                                   } as ~Runnable);
         }
     }
 

src/libstd/routine.rs

@@ -0,0 +1,28 @@
+// Copyright 2012 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/*!
+ * Routines are like closures except that they own their arguments and can
+ * only run once.
+ */
+
+/// A routine that takes no arguments and returns nothing.
+pub trait Runnable {
+    /// The entry point for the routine.
+    fn run(~self);
+}
+
+/// A convenience routine that does nothing.
+pub struct NoOpRunnable;
+
+impl Runnable for NoOpRunnable {
+    fn run(~self) {}
+}
+

src/libstd/std.rs

@@ -189,7 +189,7 @@ pub mod reflect;
 pub mod condition;
 pub mod logging;
 pub mod util;
-
+pub mod routine;
 
 /* Unsupported interfaces */
 

src/libstd/unstable/extfmt.rs

@@ -158,11 +158,14 @@ pub mod ct {
 
     // A fragment of the output sequence
     #[deriving(Eq)]
-    pub enum Piece { PieceString(~str), PieceConv(Conv), }
+    pub enum Piece {
+        PieceString(~str),
+        PieceConv(Conv),
+    }
 
-    pub type ErrorFn = @fn(&str) -> !;
+    pub type ErrorFn<'self> = &'self fn(&str) -> !;
 
-    pub fn parse_fmt_string(s: &str, err: ErrorFn) -> ~[Piece] {
+    pub fn parse_fmt_string<'a>(s: &str, err: ErrorFn<'a>) -> ~[Piece] {
         fn push_slice(ps: &mut ~[Piece], s: &str, from: uint, to: uint) {
             if to > from {
                 ps.push(PieceString(s.slice(from, to).to_owned()));
@@ -185,7 +188,10 @@ pub mod ct {
                     i += 1;
                 } else {
                     push_slice(&mut pieces, s, h, i - 1);
-                    let Parsed {val, next} = parse_conversion(s, i, lim, err);
+                    let Parsed {
+                        val,
+                        next
+                    } = parse_conversion(s, i, lim, |s| err(s));
                     pieces.push(val);
                     i = next;
                 }
@@ -224,8 +230,8 @@ pub mod ct {
         }
     }
 
-    pub fn parse_conversion(s: &str, i: uint, lim: uint, err: ErrorFn) ->
-        Parsed<Piece> {
+    pub fn parse_conversion<'a>(s: &str, i: uint, lim: uint, err: ErrorFn<'a>)
+                                -> Parsed<Piece> {
         let param = parse_parameter(s, i, lim);
         // avoid copying ~[Flag] by destructuring
         let Parsed {val: flags_val, next: flags_next} = parse_flags(s,
@@ -308,8 +314,8 @@ pub mod ct {
         }
     }
 
-    pub fn parse_type(s: &str, i: uint, lim: uint, err: ErrorFn) ->
-        Parsed<Ty> {
+    pub fn parse_type<'a>(s: &str, i: uint, lim: uint, err: ErrorFn<'a>)
+                          -> Parsed<Ty> {
         if i >= lim { err("missing type in conversion"); }
 
         // FIXME (#2249): Do we really want two signed types here?

src/libsyntax/ext/fmt.rs

@@ -38,7 +38,7 @@ pub fn expand_syntax_ext(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
     fn parse_fmt_err_(cx: @ExtCtxt, sp: Span, msg: &str) -> ! {
         cx.span_fatal(sp, msg);
     }
-    let parse_fmt_err: @fn(&str) -> ! = |s| parse_fmt_err_(cx, fmtspan, s);
+    let parse_fmt_err: &fn(&str) -> ! = |s| parse_fmt_err_(cx, fmtspan, s);
     let pieces = parse_fmt_string(fmt, parse_fmt_err);
     MRExpr(pieces_to_expr(cx, sp, pieces, args))
 }

src/libsyntax/fold.rs

@@ -869,35 +869,19 @@ mod test {
     use parse::token;
     use print::pprust;
     use super::*;
-
-    struct IdentFolder {
-        f: @fn(ast::ident)->ast::ident,
-    }
-
-    impl ast_fold for IdentFolder {
-        fn fold_ident(@self, i: ident) -> ident {
-            (self.f)(i)
-        }
-    }
-
-    // taken from expand
-    // given a function from idents to idents, produce
-    // an ast_fold that applies that function:
-    pub fn fun_to_ident_folder(f: @fn(ast::ident)->ast::ident) -> @ast_fold {
-        @IdentFolder {
-            f: f,
-        } as @ast_fold
-    }
-
+    
     // this version doesn't care about getting comments or docstrings in.
     fn fake_print_crate(s: @pprust::ps, crate: &ast::Crate) {
         pprust::print_mod(s, &crate.module, crate.attrs);
     }
 
     // change every identifier to "zz"
-    pub fn to_zz() -> @fn(ast::Ident)->ast::Ident {
-        let zz_id = token::str_to_ident("zz");
-        |_id| {zz_id}
+    struct ToZzIdentFolder;
+
+    impl ast_fold for ToZzIdentFolder {
+        fn fold_ident(&self, _: ident) -> ident {
+            token::str_to_ident("zz")
+        }
     }
 
     // maybe add to expand.rs...
@@ -917,7 +901,7 @@ mod test {
 
     // make sure idents get transformed everywhere
     #[test] fn ident_transformation () {
-        let zz_fold = fun_to_ident_folder(to_zz());
+        let zz_fold = ToZzIdentFolder;
         let ast = string_to_crate(@"#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}");
         assert_pred!(matches_codepattern,
                      "matches_codepattern",
@@ -928,7 +912,7 @@ mod test {
 
     // even inside macro defs....
     #[test] fn ident_transformation_in_defs () {
-        let zz_fold = fun_to_ident_folder(to_zz());
+        let zz_fold = ToZzIdentFolder;
         let ast = string_to_crate(@"macro_rules! a {(b $c:expr $(d $e:token)f+
 => (g $(d $d $e)+))} ");
         assert_pred!(matches_codepattern,
@@ -940,7 +924,7 @@ mod test {
 
     // and in cast expressions... this appears to be an existing bug.
     #[test] fn ident_transformation_in_types () {
-        let zz_fold = fun_to_ident_folder(to_zz());
+        let zz_fold = ToZzIdentFolder;
         let ast = string_to_crate(@"fn a() {let z = 13 as int;}");
         assert_pred!(matches_codepattern,
                      "matches_codepattern",