rust/src/libsyntax/ext/auto_encode.rs
Huon Wilson cc760a647a syntax: modernise attribute handling in syntax::attr.
This does a number of things, but especially dramatically reduce the
number of allocations performed for operations involving attributes/
meta items:

- Converts ast::meta_item & ast::attribute and other associated enums
  to CamelCase.
- Converts several standalone functions in syntax::attr into methods,
  defined on two traits AttrMetaMethods & AttributeMethods. The former
  is common to both MetaItem and Attribute since the latter is a thin
  wrapper around the former.
- Deletes functions that are unnecessary due to iterators.
- Converts other standalone functions to use iterators and the generic
  AttrMetaMethods rather than allocating a lot of new vectors (e.g. the
  old code would have to allocate a new vector to use functions that
  operated on &[meta_item] on &[attribute].)
- Moves the core algorithm of the #[cfg] matching to syntax::attr,
  similar to find_inline_attr and find_linkage_metas.

This doesn't have much of an effect on the speed of #[cfg] stripping,
despite hugely reducing the number of allocations performed; presumably
most of the time is spent in the ast folder rather than doing attribute
checks.

Also fixes the Eq instance of MetaItem_ to correctly ignore spaces, so
that `rustc --cfg 'foo(bar)'` now works.
2013-07-20 01:06:16 +10:00

36 lines
1.1 KiB
Rust

// 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.
/// Deprecated #[auto_encode] and #[auto_decode] syntax extensions
use ast;
use codemap::span;
use ext::base::*;
pub fn expand_auto_encode(
cx: @ExtCtxt,
span: span,
_mitem: @ast::MetaItem,
in_items: ~[@ast::item]
) -> ~[@ast::item] {
cx.span_err(span, "`#[auto_encode]` is deprecated, use `#[deriving(Encodable)]` instead");
in_items
}
pub fn expand_auto_decode(
cx: @ExtCtxt,
span: span,
_mitem: @ast::MetaItem,
in_items: ~[@ast::item]
) -> ~[@ast::item] {
cx.span_err(span, "`#[auto_decode]` is deprecated, use `#[deriving(Decodable)]` instead");
in_items
}