From: RichardOnRails <RichardDummyMailbox58407@...>
Date: 2009-11-13T15:25:04+09:00
Subject: Re: DRYing a Regex

On Nov 12, 6:50 pm, James Edward Gray II <ja...@graysoftinc.com>
wrote:
> On Nov 12, 2009, at 5:00 PM, RichardOnRails wrote:
>
>
>
> > I've got a routine that works fine at building an array of upper-case
> > strings extracted from a string:
>
> > aNewList = []
> > s = StringScanner.new sNewList
> > upper = /[A-Z]+/
> > not_upper= Regexp.new(  upper.source.sub( /\[/, '[^' )  )
> > while not s.eos?
> >  case
> >     when s.skip(upper); aNewList << s.matched
> >     else s.skip(not_upper)
> >  end
> > end
>
> > But the not_upper Regexp definition is really a kludge.  It somewhat
> > camouflages what is really /[^A-Z]+/
>
> > I'd like to DRY it by expressing it as something like !upper.  I need
> > something like !~ we use normally with string searches.
>
> > Any ideas?
>
> Well, you don't really need a StringScanner for this simple task.  Your code really just rebuilds String#scan():
>
>   a_new_list = s_new_list.scan(/[A-Z]+/)
>
> Note that I've also switched your variable naming style to the snake_case that we Rubyists prefer.
>
> Hope that helps.
>
> James Edward Gray II

Hi James,

As I said to Caleb, cutting my 10-liner down to 1 is extreme DRYing!!
Thanks for that.

As far as underscoring vs. Camel-case goes,  I know Rubyists'
preference, but I bow to Shakespeare's notion that "a rose by any
other name is just as sweet."  I spent a couple decades writing/
maintaining Window's application for clients using C and C++, so I've
a fondness for Polish notation (at least that's what I think it was
called.) Typing extra hyphens vs pressing the shift key lets me write
code faster, and the a/s/h prefix for arrays/strings/hashes helps me
avoid a lot of interpreter complaints.  And fellow programmers of
almost any stripe knows what I mean.  Finally,  I retired curmudgeon,
and you know how we old folks are :-)

Seriously,  your insight was very helpful and will help me avoid a
bunch of wasteful code.

Best wishes,
Richard