>From [email protected] Fri Sep 4 15:52:58 2009 X-Barracuda-Envelope-From: [email protected] Subject: Re: [r6rs-discuss] Proposed features for small Scheme, part 1: a stake in the ground From: Thomas Lord <[email protected]> To: Brian Harvey <[email protected]> Cc: [email protected], [email protected], [email protected] In-reply-to: <[email protected]> References: <[email protected]> Date: Fri, 04 Sep 2009 15:52:32 -0700 X-Barracuda-Connect: smtp150.iad.emailsrvr.com[207.97.245.150] X-Barracuda-Start-Time: 1252104755 X-Barracuda-Virus-Scanned: by EECS Spam Firewall at EECS.Berkeley.EDU
Lord: >> It certainly wouldn't be my ideal choice, because it has multiple >> return values, a blasphemy. >Why do you say that, please? >It just seems a clean symmetry to have those. and: >> there are one or two things not in any Scheme >> standard, and not implementable on top of any >> Scheme standard afaik, that I keep missing, e.g., ARITY. >What do you mean? Do you mean a procedure that >tells you the arity of a procedure? If so, >I think that is a confused notion because in general >every procedure takes a flat environment as argument [...] I think (but I'm not 100% sure) that both of these disagreements come from the same root cause: You think of a procedure as a way to get a computer to do something, and I think of a procedure as the closest we can get in this imperfect world to the Platonic ideal of a procedure, which is a mathematical function. Functions have one return value, by definition. The case for arity (and yes, I mean what you said) is less clear-cut, but /most/ mathematical functions have a simple arity either fixed or infinitely flexible -- and even then it's generally modeled as a function of one argument that can be an arbitrary-size vector. I can't think of any functions in the mathematical literature that take only prime numbers of arguments. _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
