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|
error[E0631]: type mismatch in function arguments
--> $DIR/suggest-option-asderef.rs:25:52
|
LL | fn takes_str(_: &str) -> Option<()> {
| ----------------------------------- found signature defined here
...
LL | let _: Option<()> = produces_string().and_then(takes_str);
| -------- ^^^^^^^^^ expected due to this
| |
| required by a bound introduced by this call
|
= note: expected function signature `fn(String) -> _`
found function signature `fn(&str) -> _`
note: required by a bound in `Option::<T>::and_then`
--> $SRC_DIR/core/src/option.rs:LL:COL
help: consider wrapping the function in a closure
|
LL | let _: Option<()> = produces_string().and_then(|arg0: String| takes_str(/* &str */));
| ++++++++++++++ ++++++++++++
help: call `Option::as_deref()` first
|
LL | let _: Option<()> = produces_string().as_deref().and_then(takes_str);
| +++++++++++
error[E0631]: type mismatch in function arguments
--> $DIR/suggest-option-asderef.rs:29:55
|
LL | fn takes_str(_: &str) -> Option<()> {
| ----------------------------------- found signature defined here
...
LL | let _: Option<Option<()>> = produces_string().map(takes_str);
| --- ^^^^^^^^^ expected due to this
| |
| required by a bound introduced by this call
|
= note: expected function signature `fn(String) -> _`
found function signature `fn(&str) -> _`
note: required by a bound in `Option::<T>::map`
--> $SRC_DIR/core/src/option.rs:LL:COL
help: consider wrapping the function in a closure
|
LL | let _: Option<Option<()>> = produces_string().map(|arg0: String| takes_str(/* &str */));
| ++++++++++++++ ++++++++++++
help: call `Option::as_deref()` first
|
LL | let _: Option<Option<()>> = produces_string().as_deref().map(takes_str);
| +++++++++++
error[E0631]: type mismatch in function arguments
--> $DIR/suggest-option-asderef.rs:33:55
|
LL | fn takes_str_mut(_: &mut str) -> Option<()> {
| ------------------------------------------- found signature defined here
...
LL | let _: Option<Option<()>> = produces_string().map(takes_str_mut);
| --- ^^^^^^^^^^^^^ expected due to this
| |
| required by a bound introduced by this call
|
= note: expected function signature `fn(String) -> _`
found function signature `fn(&mut str) -> _`
note: required by a bound in `Option::<T>::map`
--> $SRC_DIR/core/src/option.rs:LL:COL
help: consider wrapping the function in a closure
|
LL | let _: Option<Option<()>> = produces_string().map(|arg0: String| takes_str_mut(/* &mut str */));
| ++++++++++++++ ++++++++++++++++
help: call `Option::as_deref_mut()` first
|
LL | let _: Option<Option<()>> = produces_string().as_deref_mut().map(takes_str_mut);
| +++++++++++++++
error[E0631]: type mismatch in function arguments
--> $DIR/suggest-option-asderef.rs:39:40
|
LL | fn generic_ref<T>(_: &T) -> Option<()> {
| -------------------------------------- found signature defined here
...
LL | let _ = produces_string().and_then(generic_ref);
| -------- ^^^^^^^^^^^ expected due to this
| |
| required by a bound introduced by this call
|
= note: expected function signature `fn(String) -> _`
found function signature `fn(&_) -> _`
note: required by a bound in `Option::<T>::and_then`
--> $SRC_DIR/core/src/option.rs:LL:COL
help: consider wrapping the function in a closure
|
LL | let _ = produces_string().and_then(|arg0: String| generic_ref(&arg0));
| ++++++++++++++ +++++++
help: consider adjusting the signature so it does not borrow its argument
|
LL - fn generic_ref<T>(_: &T) -> Option<()> {
LL + fn generic_ref<T>(_: T) -> Option<()> {
|
help: call `Option::as_deref()` first
|
LL | let _ = produces_string().as_deref().and_then(generic_ref);
| +++++++++++
error: aborting due to 4 previous errors
For more information about this error, try `rustc --explain E0631`.
|
