From: Robert Klemme <shortcutter@...>
Date: 2007-11-23T03:30:00+09:00
Subject: Re: Checking whether a string is a number in disguise?

2007/11/22, Peter Bunyan <peter.bunyan@gmail.com>:
> I'm working on an RPN calculator (don't ask why...) and I'm having
> trouble getting a number from gets - how am I supposed to know whether
> it's a number?
>
> At the moment I'm doing [eval(oper) == oper.to_f], which is far from
> ideal. Any ideas? You all get to win my calculator if you know of a
> better way :D.

str = gets # chomp is not needed for Float
num = Float(str) rescue nil

if num
  puts "I'm a number: #{num}"
end

Cheers

robert

-- 
use.inject do |as, often| as.you_can - without end