From: Mike Stok <mike@...>
Date: 2006-05-12T12:20:48+09:00
Subject: Re: conversion issues

On 11-May-06, at 10:57 PM, corey konrad wrote:

> yeah i like your way alot better than num = Integer(STDIN.gets) rescue
> nil
>
>
>
> Guest wrote:
>> corey konrad wrote:
>>>> because it needs to be a string when you print it.
>>>
>>> oh ok that makes sense, isnt there a getn method for getting  
>>> number or
>>> other data types or do i always have to use gets?
>>
>> There could be:
>>
>> irb(main):001:0> def getn
>> irb(main):002:1> foo = gets
>> irb(main):003:1> foo.to_i
>> irb(main):004:1> end
>> => nil

That depends on how you want to handle errors, with this  
implementation of getn
garbage input gets turned into 0 (which you may or may not want to  
happen.)

You don't need the STDIN, or the rescue, so you can pick whichever  
you deem appropriate for your situation:

   num = gets.to_i	# decimals only, bad input => 0
   num = Integer(gets)	# handles 0x, 0, 0b prefixes, bad input =>  
ArgumentError
   num = Integer(gets) rescue nil	# as above but bad input => nil

And scanf is very useful for a raft of more complex cases (where you  
might want a C style scanf :-)

What is appropriate depends on what you are trying to do.

Mike

-- 

Mike Stok <mike@stok.ca>
http://www.stok.ca/~mike/

The "`Stok' disclaimers" apply.