"Useless syntax sugar": Numbered block parameters in Ruby

Re:"Useless syntax sugar": Numbered block parameters in Ruby by drewbug01 on Wednesday October 11, 2023 @11:02AM (#37845335)

Ruby does allow you to pass a one-parameter function as the argument to `map`:

  irb(main):001:0> ["foo", "bar"].map(&:reverse)
  => ["oof", "rab"]

Not precisely the same as what you've outlined, of course, but perhaps useful nonetheless.

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Re:"Useless syntax sugar": Numbered block parameters in Ruby by inopinatus on Thursday October 12, 2023 @12:28AM (#37853495)

Fun fact, the arity of functions generated by Symbol#to_proc is not 1 but -2 (that is, additional arguments are passed through as well), so we can write stuff like

    module MissionControl
      #...
    
      [Proc, Method, Binding, UnboundMethod].each_with_object(self, &:include)
    end

if one were so inclined.

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Re:"Useless syntax sugar": Numbered block parameters in Ruby by drewbug01 on Thursday October 12, 2023 @02:54PM (#37861413)

Huh - truly did not know about _negative_ arity in Ruby, and what that actually means. I learned something today, thank you!

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