31 lines
1.0 KiB
Rust
31 lines
1.0 KiB
Rust
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// Copyright 2015 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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pub enum Expr<'var, VAR> {
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Let(Box<Expr<'var, VAR>>,
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Box<for<'v: 'var> Fn(Expr<'v, VAR>) -> Expr<'v, VAR> + 'var>)
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}
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pub fn add<'var, VAR>
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(a: Expr<'var, VAR>, b: Expr<'var, VAR>) -> Expr<'var, VAR> {
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loop {}
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}
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pub fn let_<'var, VAR, F: for<'v: 'var> Fn(Expr<'v, VAR>) -> Expr<'v, VAR>>
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(a: Expr<'var, VAR>, b: F) -> Expr<'var, VAR> {
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loop {}
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}
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fn main() {
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let ex = (|x| {
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let_(add(x,x), |y| { //~ ERROR unable to infer enough type information about `_`
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let_(add(x, x), |x|x)})});
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}
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