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