From: dblack@...
Date: 2006-03-17T05:39:36+09:00
Subject: Re: specify a mandatory block parameter

Hi --

On Fri, 17 Mar 2006, Jeffrey Schwab wrote:

> Shea Martin wrote:
>> I think I know the answer to this already, but...
>> 
>> Is there a what to make a block parameter mandatory?
>> 
>> <code>
>> def no_block( p_str )
>>     puts "#{p_str}"
>> end
>> 
>> def block( &p_block )
>>     puts "#{p_block}"
>> end
>> 
>> no_block #this will cause an exception
>> block #this doesn't, but is still missing parameter?
>> </code>
>> 
>> I know, I could just raise my own exception if p_block == nil, just 
>> wondering why the difference?  Or am I wrong?
>
> Do you mean something like this?
>
> def f
>    throw "D'oh!  No block." unless block_given?

I think you mean "raise" :-)


David

-- 
David A. Black (dblack@wobblini.net)
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