Specify that range patterns must be nonempty. #2093
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This changes the reference to match the behavior of the compiler, based on my empirical testing. See also rust-lang/rust#149165
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| That is, in `a..=b`, a ≤ b must be the case. | ||
| For example, it is an error to have a range pattern `10..=0`. | ||
| r[patterns.range.constraint-nonempty] | ||
| A range pattern must match at least one possible value. In other words: |
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The wording here seemed little strange to me. Does this make sense? Obviously range patterns that are outside the range of the scrutinee won't match the value at all.
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| A range pattern must match at least one possible value. In other words: | |
| A range pattern must be able to match at least one possible value. In other words: |
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I wrote it this way to be consistent with the other lines in this section, for example:
The exclusive range pattern matches all values from the lower bound up to, but not including the upper bound.
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This changes the reference to match the behavior of the compiler, based on my empirical testing.
See also rust-lang/rust#149165