Esteban Küber 6c3879d1f1 Provide context when ? can't be called because of Result<_, E> ... When a method chain ending in `?` causes an E0277 because the expression's `Result::Err` variant doesn't have a type that can be converted to the `Result<_, E>` type parameter in the return type, provide additional context of which parts of the chain can and can't support the `?` operator. ``` error[E0277]: `?` couldn't convert the error to `String` --> $DIR/question-mark-result-err-mismatch.rs:28:25 | LL | fn bar() -> Result<(), String> { | ------------------ expected `String` because of this LL | let x = foo(); | ----- this can be annotated with `?` because it has type `Result<String, String>` LL | let one = x LL | .map(|s| ()) | ----------- this can be annotated with `?` because it has type `Result<(), String>` LL | .map_err(|_| ())?; | ---------------^ the trait `From<()>` is not implemented for `String` | | | this can't be annotated with `?` because it has type `Result<(), ()>` | = note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait = help: the following other types implement trait `From<T>`: <String as From<char>> <String as From<Box<str>>> <String as From<Cow<'a, str>>> <String as From<&str>> <String as From<&mut str>> <String as From<&String>> = note: required for `Result<(), String>` to implement `FromResidual<Result<Infallible, ()>>` ``` Fix #72124.		2023-12-05 22:22:08 +00:00
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issue-45124.rs
try-block-bad-lifetime.rs
try-block-bad-lifetime.stderr
try-block-bad-type.rs
try-block-bad-type.stderr	Provide context when ? can't be called because of Result<_, E>	2023-12-05 22:22:08 +00:00
try-block-catch.rs
try-block-catch.stderr	Show number in error message even for one error	2023-11-24 19:15:52 +01:00
try-block-in-edition2015.rs
try-block-in-edition2015.stderr
try-block-in-match.rs
try-block-in-return.rs
try-block-in-while.rs
try-block-in-while.stderr	Show number in error message even for one error	2023-11-24 19:15:52 +01:00
try-block-maybe-bad-lifetime.rs
try-block-maybe-bad-lifetime.stderr
try-block-opt-init.rs
try-block-opt-init.stderr	Show number in error message even for one error	2023-11-24 19:15:52 +01:00
try-block-type-error.rs
try-block-type-error.stderr
try-block-unreachable-code-lint.rs
try-block-unreachable-code-lint.stderr
try-block-unused-delims.fixed
try-block-unused-delims.rs
try-block-unused-delims.stderr
try-block.rs
try-is-identifier-edition2015.rs