diff options
| -rw-r--r-- | exercises/15_traits/traits3.rs | 15 | ||||
| -rw-r--r-- | rustlings-macros/info.toml | 9 | ||||
| -rw-r--r-- | solutions/15_traits/traits3.rs | 37 |
3 files changed, 48 insertions, 13 deletions
diff --git a/exercises/15_traits/traits3.rs b/exercises/15_traits/traits3.rs index 66da235..c244650 100644 --- a/exercises/15_traits/traits3.rs +++ b/exercises/15_traits/traits3.rs @@ -1,9 +1,8 @@ -// Your task is to implement the Licensed trait for both structures and have -// them return the same information without writing the same function twice. -// -// Consider what you can add to the Licensed trait. - trait Licensed { + // TODO: Add a default implementation for `licensing_info` so that + // implementors like the two structs below can share that default behavior + // without repeating the function. + // The default license information should be the string "Default license". fn licensing_info(&self) -> String; } @@ -15,8 +14,8 @@ struct OtherSoftware { version_number: String, } -impl Licensed for SomeSoftware {} // Don't edit this line -impl Licensed for OtherSoftware {} // Don't edit this line +impl Licensed for SomeSoftware {} // Don't edit this line. +impl Licensed for OtherSoftware {} // Don't edit this line. fn main() { // You can optionally experiment here. @@ -28,7 +27,7 @@ mod tests { #[test] fn is_licensing_info_the_same() { - let licensing_info = String::from("Some information"); + let licensing_info = "Default license"; let some_software = SomeSoftware { version_number: 1 }; let other_software = OtherSoftware { version_number: "v2.0.0".to_string(), diff --git a/rustlings-macros/info.toml b/rustlings-macros/info.toml index f5dd82a..92e440a 100644 --- a/rustlings-macros/info.toml +++ b/rustlings-macros/info.toml @@ -772,11 +772,12 @@ the value is owned anyway.""" name = "traits3" dir = "15_traits" hint = """ -Traits can have a default implementation for functions. Structs that implement -the trait can then use the default version of these functions if they choose not -to implement the function themselves. +Traits can have a default implementation for functions. Data types that +implement the trait can then use the default version of these functions +if they choose not to implement the function themselves. -See the documentation at: https://doc.rust-lang.org/book/ch10-02-traits.html#default-implementations""" +Related section in The Book: +https://doc.rust-lang.org/book/ch10-02-traits.html#default-implementations""" [[exercises]] name = "traits4" diff --git a/solutions/15_traits/traits3.rs b/solutions/15_traits/traits3.rs index 4e18198..3d8ec85 100644 --- a/solutions/15_traits/traits3.rs +++ b/solutions/15_traits/traits3.rs @@ -1 +1,36 @@ -// Solutions will be available before the stable release. Thank you for testing the beta version 🥰 +trait Licensed { + fn licensing_info(&self) -> String { + "Default license".to_string() + } +} + +struct SomeSoftware { + version_number: i32, +} + +struct OtherSoftware { + version_number: String, +} + +impl Licensed for SomeSoftware {} +impl Licensed for OtherSoftware {} + +fn main() { + // You can optionally experiment here. +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn is_licensing_info_the_same() { + let licensing_info = "Default license"; + let some_software = SomeSoftware { version_number: 1 }; + let other_software = OtherSoftware { + version_number: "v2.0.0".to_string(), + }; + assert_eq!(some_software.licensing_info(), licensing_info); + assert_eq!(other_software.licensing_info(), licensing_info); + } +} |