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// Copyright 2017 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 struct Nullable<T: NotNull>(T);
pub trait NotNull {}
pub trait IntoNullable {
type Nullable;
}
impl<T: NotNull> IntoNullable for T {
type Nullable = Nullable<T>;
}
impl<T: NotNull> IntoNullable for Nullable<T> {
type Nullable = Nullable<T>;
}
pub trait Expression {
type SqlType;
}
pub trait Column: Expression {}
#[derive(Debug, Copy, Clone)]
//~^ ERROR the trait bound `<Col as Expression>::SqlType: NotNull` is not satisfied
pub enum ColumnInsertValue<Col, Expr> where
Col: Column,
Expr: Expression<SqlType=<Col::SqlType as IntoNullable>::Nullable>,
{
Expression(Col, Expr),
Default(Col),
}
fn main() {}
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