rust/src/libstd/thunk.rs
Aaron Turon 2b3477d373 libs: merge librustrt into libstd
This commit merges the `rustrt` crate into `std`, undoing part of the
facade. This merger continues the paring down of the runtime system.

Code relying on the public API of `rustrt` will break; some of this API
is now available through `std::rt`, but is likely to change and/or be
removed very soon.

[breaking-change]
2014-12-18 23:31:34 -08:00

53 lines
1.2 KiB
Rust

// Copyright 2014 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 alloc::boxed::Box;
use core::kinds::Send;
use core::ops::FnOnce;
pub struct Thunk<A=(),R=()> {
invoke: Box<Invoke<A,R>+Send>
}
impl<R> Thunk<(),R> {
pub fn new<F>(func: F) -> Thunk<(),R>
where F : FnOnce() -> R, F : Send
{
Thunk::with_arg(move|: ()| func())
}
}
impl<A,R> Thunk<A,R> {
pub fn with_arg<F>(func: F) -> Thunk<A,R>
where F : FnOnce(A) -> R, F : Send
{
Thunk {
invoke: box func
}
}
pub fn invoke(self, arg: A) -> R {
self.invoke.invoke(arg)
}
}
pub trait Invoke<A=(),R=()> {
fn invoke(self: Box<Self>, arg: A) -> R;
}
impl<A,R,F> Invoke<A,R> for F
where F : FnOnce(A) -> R
{
fn invoke(self: Box<F>, arg: A) -> R {
let f = *self;
f(arg)
}
}