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a939bad513
When encountering an `if let` tail expression without an `else` arm for an
enum with a single variant, suggest writing an irrefutable `let` binding
instead.
```
error[E0317]: `if` may be missing an `else` clause
--> $DIR/irrefutable-if-let-without-else.rs:8:5
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LL | fn foo(x: Enum) -> i32 {
| --- expected `i32` because of this return type
LL | / if let Enum::Variant(value) = x {
LL | | value
LL | | }
| |_____^ expected `i32`, found `()`
|
= note: `if` expressions without `else` evaluate to `()`
= help: consider adding an `else` block that evaluates to the expected type
help: consider using an irrefutable `let` binding instead
|
LL ~ let Enum::Variant(value) = x;
LL ~ value
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```
Fix #61788.
29 lines
620 B
Rust
29 lines
620 B
Rust
// run-rustfix
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enum Enum {
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Variant(i32),
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}
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struct Struct(i32);
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fn foo(x: Enum) -> i32 {
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if let Enum::Variant(value) = x { //~ ERROR `if` may be missing an `else` clause
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value
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}
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}
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fn bar(x: Enum) -> i32 {
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if let Enum::Variant(value) = x { //~ ERROR `if` may be missing an `else` clause
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let x = value + 1;
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x
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}
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}
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fn baz(x: Struct) -> i32 {
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if let Struct(value) = x { //~ ERROR `if` may be missing an `else` clause
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let x = value + 1;
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x
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}
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}
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fn main() {
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let _ = foo(Enum::Variant(42));
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let _ = bar(Enum::Variant(42));
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let _ = baz(Struct(42));
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}
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