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// Copyright 2013 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.
use ast::{meta_item, item, expr};
use codemap::span;
use ext::base::ExtCtxt;
use ext::build::AstBuilder;
use ext::deriving::generic::*;
pub fn expand_deriving_eq(cx: @ExtCtxt,
span: span,
mitem: @meta_item,
in_items: ~[@item]) -> ~[@item] {
// structures are equal if all fields are equal, and non equal, if
// any fields are not equal or if the enum variants are different
fn cs_eq(cx: @ExtCtxt, span: span, substr: &Substructure) -> @expr {
cs_and(|cx, span, _, _| cx.expr_bool(span, false),
cx, span, substr)
}
fn cs_ne(cx: @ExtCtxt, span: span, substr: &Substructure) -> @expr {
cs_or(|cx, span, _, _| cx.expr_bool(span, true),
cx, span, substr)
}
macro_rules! md (
($name:expr, $f:ident) => {
MethodDef {
name: $name,
generics: LifetimeBounds::empty(),
explicit_self: borrowed_explicit_self(),
args: ~[borrowed_self()],
ret_ty: Literal(Path::new(~["bool"])),
const_nonmatching: true,
combine_substructure: $f
},
}
);
let trait_def = TraitDef {
path: Path::new(~["std", "cmp", "Eq"]),
additional_bounds: ~[],
generics: LifetimeBounds::empty(),
methods: ~[
md!("eq", cs_eq),
md!("ne", cs_ne)
]
};
trait_def.expand(cx, span, mitem, in_items)
}
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