From: Anders Borch <spam@...>
Date: 2003-07-17T20:15:23+09:00
Subject: Re: Keyword "with"

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

/Anders