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// 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.
use ast;
use codemap::Span;
use ext::base::ExtCtxt;
use ext::base;
use parse::lexer::{new_tt_reader, Reader};
use parse::parser::Parser;
use parse::token::keywords;
pub fn expand_trace_macros(cx: &mut ExtCtxt,
sp: Span,
tt: &[ast::TokenTree])
-> base::MacResult {
let sess = cx.parse_sess();
let cfg = cx.cfg();
let tt_rdr = new_tt_reader(cx.parse_sess().span_diagnostic,
None,
tt.to_owned());
let mut rust_parser = Parser(sess, cfg.clone(), tt_rdr.dup());
if rust_parser.is_keyword(keywords::True) {
cx.set_trace_macros(true);
} else if rust_parser.is_keyword(keywords::False) {
cx.set_trace_macros(false);
} else {
cx.span_err(sp, "trace_macros! only accepts `true` or `false`");
return base::MacResult::dummy_expr();
}
rust_parser.bump();
let mut rust_parser = Parser(sess, cfg, tt_rdr.dup());
let result = rust_parser.parse_expr();
base::MRExpr(result)
}
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