Hi,

In message "[ruby-talk:17794] Re: What is Array#- ?"
    on 01/07/13, Dave Thomas <Dave / PragmaticProgrammer.com> writes:

|Matz:
|
|Wouldn't it be clearer to define a new Set type, rather than new
|operations?

Yes.  When Set is what you want, Set is the cleanest way.

But, I just wanted Array subtraction, and set-like behavior is say
side-effect of performance boost.  Array#- etc. may slow down some
programs (e.g. rubicon) significantly.  That's why I needed
performance hack.

So you can persuade me that either

  * performance is not significant for this operation.

  * there's better algorithm that makes both performance and
    duplication possible.


							matz.