#### Note: this error code is no longer emitted by the compiler.
Patterns used to bind names must be irrefutable. That is, they must guarantee
that a name will be extracted in all cases. Instead of pattern matching the
loop variable, consider using a `match` or `if let` inside the loop body. For
instance:
```compile_fail,E0005
let xs : Vec<Option<i32>> = vec![Some(1), None];
// This fails because `None` is not covered.
for Some(x) in xs {
// ...
}
```
Match inside the loop instead:
```
let xs : Vec<Option<i32>> = vec![Some(1), None];
for item in xs {
match item {
Some(x) => {},
None => {},
}
}
```
Or use `if let`:
```
let xs : Vec<Option<i32>> = vec![Some(1), None];
for item in xs {
if let Some(x) = item {
// ...
}
}
```