From: dblack@...
Date: 2006-07-09T05:05:09+09:00
Subject: Re: Alternative to the Symbol#to_proc hack

Hi --

On Sun, 9 Jul 2006, Ashley Moran wrote:

> I've always been in two minds about the Symbol#to_proc hack, it's clever but 
> adds a bit of line noise.  Then I figured you can turn it around:
>
> class String
>   def everything_in(e)
>     e.map { |u| u.send(self) }
>   end
> end
>
> > "upcase".everything_in %w( i am an array )
> => ["I", "AM", "AN", "ARRAY"]
>
> It's a bit nasty because in 1.8 it can call private methods, but I kinda like 
> it.  And it's not much use if you want to pass arguments either.

It seems a little odd to send a message to a string, and then have to
backtrack to the left, so to speak, and realize that the receiver of
the message is actually a message....   It actually feels to me like
it's entering the traditional realm of the class method:

   String.upcase_all %w{ i am an array }

(Non-existent, but a typical class-method domain case.)

Of course, I'm hopelessly non-edge -- I actually think that:

   %w{i am an array}.map {|item| item.upcase }

is logical, reads nicely left to right, and contains no line noise :-)


David

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