From: James Britt Date: 2006-07-27T03:03:23+09:00 Subject: Re: I'll have the duck! dblack@wobblini.net wrote: > ... > When it comes to the association between anything with "type" in it > and is_a?-style checking, there's a more fundamental (hypoduck?) > issue: namely, the tenacity of the assumption that type and class are > the same thing. I think that "duck typing" is an attempt to get > people away from that assumption -- but the problem is that the duck > typing concept, instead, gets reinterpreted to accomodate the > assumption. So one hears references to an object's "duck type", when > what's really being talked about is simply the object's type (i.e., > the object's capabilities and behaviors at a given point in runtime). > And as long as one speaks of a "duck type", one implies that plain old > "type" refers to something else; and the usual candidate for that is > the object's class. If you poke around Lambda the Ultimate for a bit you soon learn that notions of "type" are numerous and quite varied. The terminology gets slippery fast. -- James Britt "Blanket statements are over-rated"