From: "David A. Black" <dblack@...>
Date: 2005-10-29T00:44:29+09:00
Subject: Re: Cleaner syntax for .map (is there already a way, or ruby2 idea?)

Hi --

On Fri, 28 Oct 2005, Dave Burt wrote:

> David A. Black wrote:
>> I continue to struggle to understand what people find so horrible
>> about ary.each {|item| .... }, ary.map {|item| ... }, and so forth.
>> I'll have some more coffee and maybe I'll start to see the light....
>
> There's nothing really wrong with them, but they are verbose in simple (and
> common) cases:
>
> result = array.map {|element| element.transform }
>
> The only issue is that you're saying "element" twice when you would only say
> it once if you were describing the operation to a person.

I probably would say "element" at least twice in describing it to a
person, I think.  "Go through the array one element at a time, call
the "transform" method on the current element, and save the result to
an accumulator array" or something like that.

> Groovy's (optional) implicit parameter is the counterpoint:
>
> // Groovy:
> result = array.map { it.transform() }

<shudder/> :-)

> Tangentially, I wonder if the proposed Ruby 2 block syntax makes this
> slightly more possible.
>
> # Pseudo-Ruby 2.0:
> result = array.map -> { it.transform }

<ugh/> :-)  I hope that's more pseudo than Ruby 2 :-)


David

-- 
David A. Black
dblack@wobblini.net