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// This is a reduction of a concrete test illustrating a case that was
// annoying to Rust developer stephaneyfx (see issue #46413).
//
// With resolving issue #54556, pnkfelix hopes that the new diagnostic
// output produced by NLL helps to *explain* the semantic significance
// of temp drop order, and thus why storing the result in `x` and then
// returning `x` works.
pub struct Statement;
pub struct Rows<'stmt>(&'stmt Statement);
impl<'stmt> Drop for Rows<'stmt> {
fn drop(&mut self) {}
}
impl<'stmt> Iterator for Rows<'stmt> {
type Item = String;
fn next(&mut self) -> Option<Self::Item> {
None
}
}
fn get_names() -> Option<String> {
let stmt = Statement;
let rows = Rows(&stmt); //~ ERROR does not live long enough
rows.map(|row| row).next()
// let x = rows.map(|row| row).next();
// x
//
// Removing the map works too as does removing the Drop impl.
}
fn main() {}
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