From: Daniel Finnie <danfinnie@...>
Date: 2007-02-21T08:53:44+09:00
Subject: Re: [Facets] Range#overlap?

Which is, IMHO, correct:
 >> (4..8).include? 8.5
=> false
 >> (6...9).include? 8.5
=> true


Dan

Daniel Schierbeck wrote:
> On Wed, 2007-02-21 at 08:00 +0900, Daniel Finnie wrote:
>> I think your implementation is cleaner however the endpoints of a Range 
>> do not have to implement #succ.
>>
>> class Range
>>    def span? other
>>      include? other.first and
>>        (other.exclude_end? ? other.last < last : other.last <= last )
>>    end
>> end
> 
> I've tried that implementation, but i doesn't work if you consider this
> valid:
> 
>   (4..8).span? 6...9
> 
> Since 6...9 yields the same values as 6..8. Or am I wrong to expect the
> above?
> 
> I know #last doesn't have to support #succ, and I'd be happy to see a
> better implementation. Challenge? ;)
> 
> 
> Cheers,
> Daniel
> 
> 
>