Hi! Is that it's only use? Then why? dip can easily be formulated using non-retain stack using primitives:
For example: "a" "b" "c" [ append ] dip -> "a" "b" "c" -rot append swap 2014-05-15 22:49 GMT+02:00 Slava Pestov <sl...@factorcode.org>: > Hi Bjorn, > > The retain stack is used to implement the 'dip' combinator. > > Slava > > > On Thu, May 15, 2014 at 1:46 PM, Björn Lindqvist <bjou...@gmail.com> wrote: >> >> Hi everyone, >> >> I've been walking around in Factors VM for a while and there is a lot >> of usages and references to "the retain stack." But I can't for my >> life figure out what its purpose is or why anyone ever would want one >> when there is a perfectly good data stack already available. >> >> I only found these two posts by Slava Pestov about it: >> >> >> http://article.gmane.org/gmane.comp.lang.factor.general/1931/match=retain+stack >> >> http://factor-language.blogspot.se/2010/07/overhauling-factors-c-library-interface.html >> >> "In the future, I intend on using GC maps at call sites of Factor >> words as well, instead of spilling temporary values to the retain >> stack; then I can eliminate the retain stack altogether, freeing up a >> register. After this is done the data stack will only be used to pass >> parameters between words, and not to store temporaries within a word. >> This will allow more values to be unboxed in more situations, and it >> will improve accuracy of compiler analyses." >> >> So the retain stack is useless? Freeing up a whole register sounds >> like it should be great for performance, at least on 32 bit x86. >> >> >> -- >> mvh/best regards Björn Lindqvist >> >> >> ------------------------------------------------------------------------------ >> "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE >> Instantly run your Selenium tests across 300+ browser/OS combos. >> Get unparalleled scalability from the best Selenium testing platform >> available >> Simple to use. Nothing to install. Get started now for free." >> http://p.sf.net/sfu/SauceLabs >> _______________________________________________ >> Factor-talk mailing list >> Factor-talk@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/factor-talk > > > > ------------------------------------------------------------------------------ > "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE > Instantly run your Selenium tests across 300+ browser/OS combos. > Get unparalleled scalability from the best Selenium testing platform > available > Simple to use. Nothing to install. Get started now for free." > http://p.sf.net/sfu/SauceLabs > _______________________________________________ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk > -- mvh/best regards Björn Lindqvist ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
