rust/src/librustc/util/common.rs
2013-08-04 00:39:48 -04:00

115 lines
3.3 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.
use syntax::ast;
use syntax::codemap::{span};
use syntax::oldvisit;
use std::hashmap::HashSet;
use extra;
pub fn time<T>(do_it: bool, what: ~str, thunk: &fn() -> T) -> T {
if !do_it { return thunk(); }
let start = extra::time::precise_time_s();
let rv = thunk();
let end = extra::time::precise_time_s();
printfln!("time: %3.3f s\t%s", end - start, what);
rv
}
pub fn indent<R>(op: &fn() -> R) -> R {
// Use in conjunction with the log post-processor like `src/etc/indenter`
// to make debug output more readable.
debug!(">>");
let r = op();
debug!("<< (Result = %?)", r);
r
}
pub struct _indenter {
_i: (),
}
impl Drop for _indenter {
fn drop(&self) { debug!("<<"); }
}
pub fn _indenter(_i: ()) -> _indenter {
_indenter {
_i: ()
}
}
pub fn indenter() -> _indenter {
debug!(">>");
_indenter(())
}
pub fn field_expr(f: ast::Field) -> @ast::expr { return f.expr; }
pub fn field_exprs(fields: ~[ast::Field]) -> ~[@ast::expr] {
fields.map(|f| f.expr)
}
// Takes a predicate p, returns true iff p is true for any subexpressions
// of b -- skipping any inner loops (loop, while, loop_body)
pub fn loop_query(b: &ast::Block, p: @fn(&ast::expr_) -> bool) -> bool {
let rs = @mut false;
let visit_expr: @fn(@ast::expr,
(@mut bool,
oldvisit::vt<@mut bool>)) = |e, (flag, v)| {
*flag |= p(&e.node);
match e.node {
// Skip inner loops, since a break in the inner loop isn't a
// break inside the outer loop
ast::expr_loop(*) | ast::expr_while(*) => {}
_ => oldvisit::visit_expr(e, (flag, v))
}
};
let v = oldvisit::mk_vt(@oldvisit::Visitor {
visit_expr: visit_expr,
.. *oldvisit::default_visitor()});
oldvisit::visit_block(b, (rs, v));
return *rs;
}
// Takes a predicate p, returns true iff p is true for any subexpressions
// of b -- skipping any inner loops (loop, while, loop_body)
pub fn block_query(b: &ast::Block, p: @fn(@ast::expr) -> bool) -> bool {
let rs = @mut false;
let visit_expr: @fn(@ast::expr,
(@mut bool,
oldvisit::vt<@mut bool>)) = |e, (flag, v)| {
*flag |= p(e);
oldvisit::visit_expr(e, (flag, v))
};
let v = oldvisit::mk_vt(@oldvisit::Visitor{
visit_expr: visit_expr,
.. *oldvisit::default_visitor()});
oldvisit::visit_block(b, (rs, v));
return *rs;
}
pub fn local_rhs_span(l: @ast::Local, def: span) -> span {
match l.init {
Some(i) => return i.span,
_ => return def
}
}
pub fn pluralize(n: uint, s: ~str) -> ~str {
if n == 1 { s }
else { fmt!("%ss", s) }
}
// A set of node IDs (used to keep track of which node IDs are for statements)
pub type stmt_set = @mut HashSet<ast::NodeId>;