From: saggmannen@... (saggmannen)
Date: 2003-12-09T22:22:01+09:00
Subject: Re: format money

Gregory Millam <walker@lethalcode.net> wrote in message news:<20031208154352.7194ada5.walker@lethalcode.net>...
> Received: Tue, 9 Dec 2003 05:39:27 +0900
> And lo Peter wrote:
> 
> > > # Here's my try:
> > >
> > > balance.to_s.reverse.gsub(/(\d{3})(?=\d)/,'\1,').reverse
> > >
> > > examples:
> > > irb(main):007:0> "123456789".reverse.gsub(/(\d{3})(?=\d)/,'\1,').reverse
> > > => "123,456,789"
> > > irb(main):008:0> "1234567890".reverse.gsub(/(\d{3})(?=\d)/,'\1,').reverse
> > > => "1,234,567,890"
> > >
> > > (?=\d) is a lookahead assertion that checks to see if there's a digit
> > > ahead of the current pattern without capturing it (which is the
> > > important thing).
> > 
> > Apparently I hid my try pretty well in my reply :-)
> > 
> > Peter
> 
> *hits forehead*
> 
> Because of the ">" in irb(main):...:..>, my mua displays it as a comment.
> *continues to hit forehead*
> 
> 
> - Greg 'blind' Millam


both your solutions work fine if the number of decimals is less than
or equal to three. What if I would like more precision than that in my
output? Eg.

2111000.5567 => "2,111,000.5567"