Re: Felleisen on Standard Haskell
Simon L Peyton Jones wrote: That's just what I intend to do. I don't see Std Haskell as a big deal, but even little deals are worth completing rather than leaving as loose ends... and I'm more optimistic than Paul about the usefulness of Std Haskell. I would be happy to find a name that was less grand and final-sounding than 'Standard Haskell' though; but more final sounding than 'Haskell 1.5'. `Teaching Haskell' is an obvious option, but might put too many non-academics off. So, considering its purpose, what about `Stable Haskell'? (The main drawback is, of course, that the phrase `horses for courses' springs to mind :-) [Just couldn't resist sharing that one with you all!] -- David post: DERA Malvern, St Andrews Road, Malvern, WORCS WR14 3PS, ENGLAND mailto:[EMAIL PROTECTED] ** phone: +44 1684 895112 ** fax: +44 1684 894389 [The views expressed above are entirely those of the writer and do not represent the views, policy or understanding of any other person or official body.]
Re: Xmas fun
Fergus Henderson wrote: On 19-Dec-1997, Simon L Peyton Jones [EMAIL PROTECTED] wrote: I thought you might find the following bug I've just found in GHC entertaining. ... sameVal (AbsApproxFun str1 v1) (AbsApproxFun str2 v2) = str1 == str2 sameVal v1 v1 ... This bug could have been caught by a very simple static analysis that is very popular in the logic programming community: singleton variable warnings. In the code above, the variable `v2' occurs only once. Singleton variables such as this are often bugs. For cases where the programmer really does want a singleton variable, the warning can be suppressed by using a different naming convention (in Prolog, it would be `_v2'; since Haskell doesn't allow leading underscores, I suppose you could use `v2_'). In this case, the even simpler ``unused identifier'' warning would suffice! (Easily suppressed by the use of a wildcard pattern such as `_'.) So, sing ho for regression tests, but sing louder for static analysis ;-) Hear, hear! Merry Xmas, etc., David Bruce post: DERA Malvern, St Andrews Road, Malvern, WORCS WR14 3PS, ENGLAND mailto:[EMAIL PROTECTED] ** phone: +44 1684 895112 ** fax: +44 1684 894389 [The views expressed above are entirely those of the writer and do not represent the views, policy or understanding of any other person or official body.]
Re: article wanted
I'm searching for an article titled like "The next 10 problems in functional programming" I don't know of that one (though I would also be interested) but here are two on similar lines. Hope they are useful/interesting. Carl G Ponder, Patrick C McGeer and Anthony P-C Ng "Are Applicative Languages Inefficent?" pp 135-139 in SIGPLAN Notices, Vol. 23, No. 6, June 1988 [ Lists seven problems for which the lack of side-effects appears to impose a logarithmic inefficiency on run-time. ] Amir M Ben-Amram and Zvi Galil "On Pointers versus Addresses" pp 617-648 in J. ACM, Vol. 39, No. 3, July 1992 [ Contrasts a pointer machine with a random access machine (addresses may be computed on a RAM, but not on a PM). In general a PM incurs a logarithmic run-time factor. ] I suspect (ie. it's a gut reaction that I can't yet justify rigorously :-() that the side-effect-or-not and RAM-or-PM issues are related. David Bruce post: DRA Malvern, St Andrews Road, Malvern, Worcestershire WR14 3PS, ENGLAND email: [EMAIL PROTECTED] (internet) [EMAIL PROTECTED] (janet) phone: +44 684 895112 ** fax: +44 684 894389 or 894540 ** telex: 339747
Re: The class Ix
RFC-822-HEADERS: Original-Via: uk.ac.ucl.cs.ess; Fri, 7 Feb 92 09:55:08 GMT == I am not sure what the two versions of the first law imply. I would, however, note that the two conditions are incomparable (ie. neither implies the other). Perhaps someone can explain? David Bruce PS. In Simon's posting there is a typo: range should deliver [a], not a.
