| A lower range wasn't less than the upper range. |
| |
| Erroneous code example: |
| |
| ```compile_fail,E0579 |
| #![feature(exclusive_range_pattern)] |
| |
| fn main() { |
| match 5u32 { |
| // This range is ok, albeit pointless. |
| 1..2 => {} |
| // This range is empty, and the compiler can tell. |
| 5..5 => {} // error! |
| } |
| } |
| ``` |
| |
| When matching against an exclusive range, the compiler verifies that the range |
| is non-empty. Exclusive range patterns include the start point but not the end |
| point, so this is equivalent to requiring the start of the range to be less |
| than the end of the range. |
