From: matz@... Date: 2020-02-27T05:54:10+00:00 Subject: [ruby-core:97279] [Ruby master Feature#15722] `Kernel#case?` Issue #15722 has been updated by matz (Yukihiro Matsumoto). Status changed from Open to Feedback It is not obvious to me that `#case?` is useful. We need a real-world use-case. * I don't like the name `case?` * IMO, just use `case` statement Matz. ---------------------------------------- Feature #15722: `Kernel#case?` https://bugs.ruby-lang.org/issues/15722#change-84396 * Author: sawa (Tsuyoshi Sawada) * Status: Feedback * Priority: Normal ---------------------------------------- I often want to use `===` to match a single object on the right side against multiple objects on the left, as is used in `case`-constructions, just to return a truth value, and end up writing like this: ```ruby bar # => "bar" flag1 = case bar; when "foo", "bar", "baz"; true; end # => true flag2 = case bar; when Symbol, String; true; end # => true ``` I propose `Kernel#case?` that should work like this: ```ruby bar # => "bar" bar.case?("foo", "bar", "baz") # => true bar.case?("qux") # => false bar.case?(Symbol, String) # => true bar.case?(Array) # => false bar.case? # => false ``` It is similar to Rails' `in?`, but it differs from it in that it uses `===` for comparison, not `==`. Or, alternatively, allowing `Kernel#instance_of?` and `Kernel#kind_of?` to allow multiple arguments may be a compromise. -- https://bugs.ruby-lang.org/ Unsubscribe: