Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!nrl-cmf!cmcl2!lanl!jlg From: jlg@lanl.gov (Jim Giles) Newsgroups: comp.lang.fortran Subject: Re: *THE GENERAL CASE* (was: function side effects) Message-ID: <3980@lanl.gov> Date: 21 Sep 88 23:23:39 GMT References: <3999@h.cc.purdue.edu> Organization: Los Alamos National Laboratory Lines: 33 From article <3999@h.cc.purdue.edu>, by ags@h.cc.purdue.edu (Dave Seaman): > In article <3821@lanl.gov> jlg@lanl.gov (Jim Giles) writes: >>If you want to talk about side effects in general - fine. >>Read section 1.4 of the standard document. > > I already have. It supports my position that side effects are allowed > except where specifically prohibited. [...] Which is what I said as well. So what is the basis of your argument. I have _never_ claimed that side effects couldn't be done in the general case. Until _you_ claimed that I had, I hadn't even _mentioned_ the general case! And as for section 1.4 of the standard - I am one of the most frequent supporters of allowing extensions. As I've repeatedly pointed out: pointers, 31 character names, bit functions, etc. are all extensions allowed in CFT77 on Crays - and _NOT_ONE_ of these feartures makes the compiler non-standard. What your original position was is hard to judge. It seems to me that your original submissions were claiming that Fortran didn't prohibit side effects in _any_ context. (After all, _you_ were the one who posted the remark that functions were allowed to change their arguments. You posted that remark in response to an article in which I claimed that the functions in A(F(I))=A(F(I))+1 couldn't. Well, they _can't_!) As for having side effects in the general case - go ahead, all you want. I do it all the time. My most common method of writing non-arithmetic subroutines is to write them as functions instead and return an error flag as the function value. So I seldom write subroutines at all, and MOST of my functions have side effects - but none of them used in the original context of this discussion do! J. Giles Los Alamos