From: James Edward Gray II <james@...>
Date: 2005-04-23T00:32:16+09:00
Subject: Re: [QUIZ] HighLine (#29)

On Apr 22, 2005, at 10:12 AM, Christian Neukirchen wrote:

> Ruby Quiz <james@grayproductions.net> writes:
>
>> What I really think we need here is to take a page out of the 
>> optparse book.
>> Here are some general ideas:
>>
>> 	age = ask("What is your age?", Integer, :within => 0..105)
>> 	num = eval "0b#{ ask( 'Enter a binary number.',
>> 	                      String, :validate => /^[01_]+$/ ) }"
>
> Do not ever do that.
>
> irb(main):004:0> Integer("0b1011")
> => 11
> irb(main):005:0> "1011".to_i(2)
> => 11
>
> irb(main):006:0> "foo\nbar" =~ /^foo$/
> => 0

I'm not exactly sure what you're trying to show here.  Even 0 would be 
a fine binary number.  However, the point was that I have created a 
safe eval() because ask() should not return anything that doesn't 
validate.

Obviously, using Integer() is better style though.

James Edward Gray II