diff options
| -rw-r--r-- | src/libcore/str/mod.rs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs index 4d39607b16e..11ca6e332b5 100644 --- a/src/libcore/str/mod.rs +++ b/src/libcore/str/mod.rs @@ -44,8 +44,11 @@ pub trait FromStr { #[stable(feature = "rust1", since = "1.0.0")] type Err; - /// Parses a string `s` to return an optional value of this type. If the - /// string is ill-formatted, the None is returned. + /// Parses a string `s` to return a value of this type. + /// + /// If parsing succeeds, return the value inside `Ok`, otherwise + /// when the string is ill-formatted return an error specific to the + /// inside `Err`. The error type is specific to implementation of the trait. #[stable(feature = "rust1", since = "1.0.0")] fn from_str(s: &str) -> Result<Self, Self::Err>; } |