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Diffstat (limited to 'src/tools/clippy/src/docs/derive_ord_xor_partial_ord.txt')
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1 files changed, 0 insertions, 44 deletions
diff --git a/src/tools/clippy/src/docs/derive_ord_xor_partial_ord.txt b/src/tools/clippy/src/docs/derive_ord_xor_partial_ord.txt deleted file mode 100644 index f2107a5f6..000000000 --- a/src/tools/clippy/src/docs/derive_ord_xor_partial_ord.txt +++ /dev/null @@ -1,44 +0,0 @@ -### What it does -Checks for deriving `Ord` but implementing `PartialOrd` -explicitly or vice versa. - -### Why is this bad? -The implementation of these traits must agree (for -example for use with `sort`) so it’s probably a bad idea to use a -default-generated `Ord` implementation with an explicitly defined -`PartialOrd`. In particular, the following must hold for any type -implementing `Ord`: - -``` -k1.cmp(&k2) == k1.partial_cmp(&k2).unwrap() -``` - -### Example -``` -#[derive(Ord, PartialEq, Eq)] -struct Foo; - -impl PartialOrd for Foo { - ... -} -``` -Use instead: -``` -#[derive(PartialEq, Eq)] -struct Foo; - -impl PartialOrd for Foo { - fn partial_cmp(&self, other: &Foo) -> Option<Ordering> { - Some(self.cmp(other)) - } -} - -impl Ord for Foo { - ... -} -``` -or, if you don't need a custom ordering: -``` -#[derive(Ord, PartialOrd, PartialEq, Eq)] -struct Foo; -```
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