src/libsyntax/ext/deriving/cmp/totaleq.rs

   1 // Copyright 2013 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 use ast::{MetaItem, Item, Expr};
  12 use codemap::Span;
  13 use ext::base::ExtCtxt;
  14 use ext::build::AstBuilder;
  15 use ext::deriving::generic::*;
  16
  17 use std::vec_ng::Vec;
  18
  19 pub fn expand_deriving_totaleq(cx: &mut ExtCtxt,
  20                                span: Span,
  21                                mitem: @MetaItem,
  22                                item: @Item,
  23                                push: |@Item|) {
  24     fn cs_equals(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> @Expr {
  25         cs_and(|cx, span, _, _| cx.expr_bool(span, false),
  26                cx, span, substr)
  27     }
  28
  29     let trait_def = TraitDef {
  30         span: span,
  31         attributes: Vec::new(),
  32         path: Path::new(vec!("std", "cmp", "TotalEq")),
  33         additional_bounds: Vec::new(),
  34         generics: LifetimeBounds::empty(),
  35         methods: vec!(
  36             MethodDef {
  37                 name: "equals",
  38                 generics: LifetimeBounds::empty(),
  39                 explicit_self: borrowed_explicit_self(),
  40                 args: vec!(borrowed_self()),
  41                 ret_ty: Literal(Path::new(vec!("bool"))),
  42                 inline: true,
  43                 const_nonmatching: true,
  44                 combine_substructure: cs_equals
  45             }
  46         )
  47     };
  48     trait_def.expand(cx, mitem, item, push)
  49 }