From: Anders Borch <spam@...>
Date: 2003-07-18T02:59:00+09:00
Subject: Re: Keyword "with"

Hal E. Fulton wrote:
> ----- Original Message ----- 
> From: "Anders Borch" <spam@deck.dk>
> Newsgroups: comp.lang.ruby
> To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
> Sent: Thursday, July 17, 2003 6:15 AM
> Subject: Re: Keyword "with"
> 
> 
> 
>>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
> 
> 
> I haven't played with this at all... but let me 
> remind you that the ++ operator comes in both
> pre and post forms.
> 
> Until these code fragments both work, I'd say
> you haven't actually implemented it, even as a
> preprocessor kind of thing:
> 
>   x = 5
>   y = x++
>   puts y       # 5
> 
>   y = ++x 
>   puts y       # 6
> 
> Cheers,
> Hal
> 

I was merely showing a proof of concept (implementing pre-increment 
since that was the easy one), but if you like, I shall implement both 
pre- and postincrement. I saw the flaw you pointed out shortly after 
posting, but saw no need to complicate my implementation unless someone 
actually made the explicit distinction between the two forms of 
incrementation.

I am personally against using these tricks in any serious form (remember 
ruby goto in an earlier post?) or have you ever looked at the AND, OR, 
NOT macros defined for C? I feel no need to change the language merely 
for the sake of change. Especially when the change does not add to 
readability. AND, OR, and NOT are not very readable IMHO there is a need 
to explicitly specify && or & as logical or binary AND. The == operator 
does not really add any functionality to ruby, but it would add 
readability since *a lot* of programmers out there knows pre and post 
increment.

/Anders