diff options
| author | Kazuki Tsujimoto <kazuki@callcc.net> | 2020-12-13 11:50:14 +0900 |
|---|---|---|
| committer | Kazuki Tsujimoto <kazuki@callcc.net> | 2020-12-13 11:51:49 +0900 |
| commit | 88f3ce12d32ffbef983b0950743c20253ea2d0c6 (patch) | |
| tree | 8ff07aa837af75a4e389ef30d139fb391be63e0f /NEWS.md | |
| parent | a8cf526ae99c9e0823cd8c7c5ac96e43061fafa6 (diff) | |
Reintroduce `expr in pat` [Feature #17371]
Diffstat (limited to 'NEWS.md')
| -rw-r--r-- | NEWS.md | 24 |
1 files changed, 17 insertions, 7 deletions
@@ -52,19 +52,28 @@ sufficient information, see the ChangeLog file or Redmine instead of a warning. yield in a class definition outside of a method is now a SyntaxError instead of a LocalJumpError. [[Feature #15575]] -* Pattern matching is no longer experimental. [[Feature #17260]] +* Pattern matching(`case/in`) is no longer experimental. [[Feature #17260]] -* One-line pattern matching now uses `=>` instead of `in`. [EXPERIMENTAL] - [[Feature #17260]] +* One-line pattern matching is redesgined. [EXPERIMENTAL] + * `=>` is added. It can be used as like rightward assignment. + [[Feature #17260]] + + ```ruby + 0 => a + p a #=> 0 + + {b: 0, c: 1} => {b:} + p b #=> 0 + ``` + + * `in` is changed to return `true` or `false`. [[Feature #17371]] ```ruby # version 3.0 - {a: 0, b: 1} => {a:} - p a # => 0 + 0 in 1 #=> false # version 2.7 - {a: 0, b: 1} in {a:} - p a # => 0 + 0 in 1 #=> raise NoMatchingPatternError ``` * Find pattern is added. [EXPERIMENTAL] @@ -639,4 +648,5 @@ end [Feature #17187]: https://bugs.ruby-lang.org/issues/17187 [Bug #17221]: https://bugs.ruby-lang.org/issues/17221 [Feature #17260]: https://bugs.ruby-lang.org/issues/17260 +[Feature #17371]: https://bugs.ruby-lang.org/issues/17371 [GH-2991]: https://github.com/ruby/ruby/pull/2991 |