From: Robert Klemme <bob.news@...>
Date: 2003-07-17T22:36:38+09:00
Subject: Re: Keyword "with"


"Anders Borch" <spam@deck.dk> schrieb im Newsbeitrag
news:3F168404.2060602@deck.dk...
> Anders Borch wrote:
> > Brian Candler wrote:
> >
> >> On Thu, Jul 17, 2003 at 06:54:44PM +0900, Anders Borch wrote:
> >>
> >>> Now, any file loaded with loadpp may contain the ++ operator, and it
> >>> will be replaced with '+= 1'. Have fun with it if you like :)
> >>
> >>
> >>
> >> It might be better to replace foo++ with (foo=foo.succ) because it
> >> will work
> >> on things other than numbers - except for some reason there doesn't
> >> seem to
> >> be any 'pred', so you can't implement foo-- in this way :-(
> >>
> >> irb(main):003:0> "fred".succ
> >> => "free"
> >>
> >
> > true... I wouldn't be able to implement that in as few lines, since
> > #succ does not modify the receiver the way +=1 and ++ does.
> >
>
> actually I was wrong... gsub solves this quite nicely...
>
> def loadpp(l)
>    s = ''
>    f = File.new(l,'r')
>    f.each_line do |line|
>      s += line.gsub(/(\w)\+\+)/,'\1=\1.succ') + "\n"
>    end
>    eval(s)
> end

There's an error in the regexp.  It should read /(\w+)\+\+)/ to be able to
work with identifiers that are longer than one char.

    robert