From: Mike Stok <mike@...>
Date: 2001-11-30T07:42:08+09:00
Subject: [ruby-talk:26986] Re: first class functions in Ruby

On Fri, 30 Nov 2001, MikkelFJ wrote:

> In the thread on language design, I mentioned a wish for functions as first
> class values.
>
> I hope someone knowing Ruby deeper than I will follow up on this.
>
> I'd like to be able to write a function that I can pass as argument to a
> Ruby message or to another function. A function is a new concept in Ruby
> context.

[...]

> improved syntax:
>
> <snip>
> fun squareFunction arg
>   arg + arg
> end
> def aMessage f
>   f(42) + f(27)
> end
> def main
>   aMessage squareFunction
> end
> </snip>

What about  using a Proc object?

def aMessage(f)
    f.call(42) + f.call(27)
end

squareFunction = Proc.new { |arg|
    arg * arg
}

puts(aMessage(squareFunction))

Mike

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