32 lines
1.0 KiB
Rust
32 lines
1.0 KiB
Rust
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// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![feature(default_type_params, unboxed_closures)]
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use std::thunk::Thunk;
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pub trait Promisable: Send + Sync {}
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impl<T: Send + Sync> Promisable for T {}
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pub fn propagate<T, E, F, G>(action: F) -> Thunk<Result<T, E>, Result<T, E>>
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where
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T: Promisable + Clone,
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E: Promisable + Clone,
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F: FnOnce(&T) -> Result<T, E> + Send,
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G: FnOnce(Result<T, E>) -> Result<T, E> {
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Thunk::with_arg(move |: result: Result<T, E>| {
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match result {
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Ok(ref t) => action(t),
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Err(ref e) => Err(e.clone()),
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}
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})
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}
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fn main() {}
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