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# Error code E0030

When matching against a range, the compiler verifies that the range is non-empty. Range patterns include both end-points, so this is equivalent to requiring the start of the range to be less than or equal to the end of the range.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    match 5u32 {
        // This range is ok, albeit pointless.
        1 ..= 1 => {}
        // This range is empty, and the compiler can tell.
        1000 ..= 5 => {}
    }
    }