Is there a reason why loops using the « for » keyword are not implemented in Crystal?

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1

Is there a reason why loops using the « for » keyword are not implemented in Crystal (as opposed to Ruby)?

After all, the « for … in …. » construct is present in most modern programming languages (Python, Go, JavaScript, Swift.etc.)

2

See "For" Loop support · Issue #830 · crystal-lang/crystal · GitHub.

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3

Thanks!

4

I saw the following snippet on : Crystal for Rubyists · crystal-lang/crystal Wiki · GitHub

#for loops are not supported but you can add them via macro:

macro for(expr)
  {{expr.args.first.args.first}}.each do |{{expr.name.id}}|
    {{expr.args.first.block.body}}
  end
end

for i in [1,2,3] do
 puts i
end

It doesn’t seem to work.

It there a typo or is it just plain wrong?

5

It’s just outdated I’d say due to Let `case when` be non-exhaustive, introduce `case in` as exhaustive by asterite · Pull Request #9258 · crystal-lang/crystal · GitHub which made in a keyword. See For macro.

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