From: Trans <transfire@...>
Date: 2006-12-07T07:57:16+09:00
Subject: Re: invasive parameters as method mode variables


Robert Klemme wrote:
> On 06.12.2006 18:37, Trans wrote:
> > ara.t.howard@noaa.gov wrote:
> >
> >> method + state => object
>
> I would have put it differently: command pattern.  Your method seems
> pretty complex so you can change it into a command object.  If the
> problem at hand is complex then it probably needs a complex solution.
> But I would not go down the metaprogramming route.
>
> > good point. though it moves me away from the simplicity of single call.
> > also i wonder about things like String#each. the global default for
> > separator is not really the ideal implementation, but #each can't be
> > made a class.
>
> Really?
>
>  >> require 'enumerator'
> => true
>  >> %w{foo bar baz}.to_enum(:each)
> => #<Enumerable::Enumerator:0x3a6b00>

Sure. But I would think it preferable to just call str.each. Not have
to resort to Enumerators. Doing...

  "this is a string".to_enum(:each, //).select { |c| ..

is less efficent and less readable (once you know what $/ is) then

  $/ = // ; "this is a string".select { |c| ...

And if we can do it gloablly, which is not ideal, then why not do it
better with a local "method mode variable"?

Of course, I'm still not sure why it's such a bad idea to allow
Enumberable to pass thru a parameter to #each.

T.