From: dblack@...
Date: 2006-07-30T02:39:18+09:00
Subject: Re: to_i vs. to_int

Hi --

On Sun, 30 Jul 2006, Morton Goldberg wrote:

> On Jul 29, 2006, at 12:58 PM, dblack@wobblini.net wrote:
>
>> What's a use case for to_int?  I was thinking of this classic to_str
>> example:
>>
>>   class S
>>     def to_str
>>       "some text"
>>     end
>>   end
>>
>>   puts "Here is " + S.new   # Here is some text
>> 
>> But the to_int equivalent doesn't work:
>>
>>   class S
>>     def to_int
>>       2
>>     end
>>   end
>>
>>   puts 2 + S.new    # TypeError: S can't be coerced into Fixnum
>> 
>> Same thing with:
>>
>>   puts Integer(2) + S.new
>> 
>> I'm stuck trying to find a case where to_int does what to_str does --
>> but maybe it doesn't.
>
> However,
>
>   puts 2 + Integer(S.new) => 4
>
> uses your S#to_int

True, but it works the same with to_i, as opposed to the string one
where to_s and to_str work differently.


David

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