diff options
| -rw-r--r-- | library/core/src/str/traits.rs | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/library/core/src/str/traits.rs b/library/core/src/str/traits.rs index 85d5fa1ef92..2f425c82dc8 100644 --- a/library/core/src/str/traits.rs +++ b/library/core/src/str/traits.rs @@ -765,6 +765,12 @@ unsafe impl SliceIndex<str> for ops::RangeToInclusive<usize> { /// mistake, unless the type has provided and documented additional guarantees about its `Display` /// and `FromStr` implementations. /// +/// If a type happens to have a lossless `Display` implementation whose output is meant to be +/// conveniently machine-parseable and not just meant for human consumption, then the type may wish +/// to accept the same format in `FromStr`, and document that usage. Having both `Display` and +/// `FromStr` implementations where the result of `Display` cannot be parsed with `FromStr` may +/// surprise users. (However, the result of such parsing may not have the same value as the input.) +/// /// # Examples /// /// Basic implementation of `FromStr` on an example `Point` type: |