Path: utzoo!attcan!uunet!husc6!uwvax!oddjob!mimsy!chris From: chris@mimsy.UUCP (Chris Torek) Newsgroups: comp.lang.fortran Subject: Re: Assigned GOTO Message-ID: <12416@mimsy.UUCP> Date: 12 Jul 88 14:40:31 GMT References: <2742@utastro.UUCP> <20008@beta.UUCP> <224@raunvis.UUCP> <20664@beta.lanl.gov> Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742 Lines: 42 >In article <12362@mimsy.UUCP> I suggested doing `jump to another function without changing {stack frames / execution environments / whatever you want to call them}': >>do it in assembly: >> # jump_to, for vax: --- In article <20664@beta.lanl.gov> jlg@beta.lanl.gov (Jim Giles) writes: >Think again. My machine doesn't have any of these mnemonics. Are you deliberately being irritating? >... The requirement is for a PORTABLE way of doing the action. Not necessarily. >In this respect, a 'better way' would be to allow pointers to code, >and allow jumps to them .... Possibly so. But if you MUST use some language (perhaps it is the only one you have that is anywhere near suited to the task) and you cannot do something within that language, the best way is to do it out of that language---*AFTER* abstracting the operation, so that it can be done on other machines without too much effort. (Perhaps it will take a fair bit of effort; maybe the reason it is not in the language is because it is *hard* on some machines. The VAX version I wrote is basically wrong; a correct version is quite a bit longer.) >... But, if this method was indeed the >most efficient, then assembly is not a good substitute to having >the feature in the language. No, but changing the language to add it is also not a good substitute for having it in the language, unless you intend to convince everyone else also to change the language in the same way (and are willing to back off if the next ANSI or ISO or ... standard decides it should be done differently). (If it is your own language, of course, do whatever you like.) -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163) Domain: chris@mimsy.umd.edu Path: uunet!mimsy!chris