"Phil Boswell" <phil.boswell(a)gmail.com> wrote in message news:dnk5ht$8e6$1@sea.gmane.org... [snip] Now that I have taken another look at it, I think that it is actually doing something extremely clever. The wikicode is: {{{else{{{test|}}}|{{{test{{{test|}}}|{{{then|}}}}}}}}} You call it like this: {{qif |test=VARIABLE_OR_PARAMETER_TO_TEST |then=code if 'test' is not empty |else=code if 'test' is empty }} It relies on the relatively-recent optional value system, where {{{parameter|value}}} gives you "value" if "parameter" is blank, otherwise "parameter". So if I introduce a bit of white-space to make it easier to read the operation becomes a little more apparent: {{{ else {{{ test | }}} | {{{ test {{{ test | }}} | {{{ then | }}} }}} }}} If 'test' is empty, this reduces to: {{{ else {{{ | }}} | {{{ {{{ | }}} | {{{ then | }}} }}} }}} and thus to: {{{ else | {{{ | {{{ then | }}} }}} }}} and assuming that 'else' is non-empty this simply gives else If 'test' is *not* empty, then the original reduces to: {{{ else {{{ test }}} | {{{ test {{{ test }}} | {{{ then | }}} }}} }}} and thus to: {{{ elsetest | {{{ testtest | {{{ then | }}} }}} }}} Now 'elsetest' is perforce empty, since it's a whole new "parameter" giving: {{{ testtest | {{{ then | }}} }}} and the same goes for 'testtest': {{{ then | }}} which trivially reduces to: then Takes me back to my (admittedly brief) functional programming days and the dreaded lambda calculus :-) So whether this template is more efficient than {{if}} basically boils down to whether the Template Syntax code can perform the transformations detailed above quicker than the extra fetch which the slightly-simpler {{if}} requires, relying on the trick whereby if you specify two parameters with the same name, Mediawiki discards the first and uses the second, passing parameters to a supporting template named {{show1}}. I'm betting on the code beating the fetching by a long margin. So until we can persuade some kind developer to implement the "if" functionality in Mediawiki, I'm championing {{qif}}. It would be nice if we could retire the current version of {{if}} and re-use that name, but the nice thing about a wiki is that you can take things just about as slow as you like, provided nobody jogs your elbow. HTH HAND -- Phil [[en:User:Phil Boswell]]

-----BEGIN PGP SIGNED MESSAGE----- Moin, On Monday 12 December 2005 18:59, Phil Boswell wrote: [snip a lot] While clever, that doesn't mean it is good. Not every thing you can do, you also should do. :) I you thought that script languages like Perl, PHP, phyton, etc were slow, then this system has to beat them hands down. I can't even imagine how much CPU cycles must be burned for such a thing. Thank god it is only executed on rendering the page, once, and not for every view. I can see it now: * After {{{qif}}, somebody implements loops. * Soon lexial scoping, the switch statement and subroutines follow. * 5 days later the wiki-template system is turing-complete. * 2 days later a careless placed "{" triggers an endless loop and brings wikipedia down for 2 3/4 hours, until the bug is fixed. * 1 hour later JoeCleverProgrammer posts his brainfuck-interpreter, done entirely with "clever" templates in wikitext. * a week later the first page consisting only of curly braces, the pipe symbol, spaces and newlines is spotted. When viewed in a browser, it renders as "kilroy was here", due to a clever abuse of templates, variables, bugs and some unrelated accident involving a pound of butter, a slippery server room floor and an unfortunately placed button. Joking aside, IMHO, if that sort of (ab)use of templates continues, soon the only people qualified to edit pages will be programmers. The wikisyntax is a success because it is so easy and maintainable/readable by mere humans. Crafting "clever" systems on top of it will merely make normal humans go away as they will not be able to understand this stuff even after staring on the curly mess for an hour. Case in point is that regular contributors to smaller wikis already struggle with the table syntax or even simple templates. Variable substitution and conditional template inclusion will break their little minds. Best wishes, Tels - -- Signed on Mon Dec 12 21:27:19 2005 with key 0x93B84C15. Visit my photo gallery at http://bloodgate.com/photos/ PGP key on http://bloodgate.com/tels.asc or per email. "Elliot, Sie Schwachkopf!"

On 12/13/05, Adrian Buehlmann <adrian(a)cadifra.com> wrote: It might be a good idea to protect all of those templates to prevent horrible consequences in the event of vandalism. If the syntax is really stable, then there shouldn't be any problems with that. -- Stephen Bain stephen.bain(a)gmail.com

Phil Boswell wrote: For quite some time (1973-1993 or so), the Unix/Linux commands test(1), true(1) and false(1) were stand-alone programs that required the fork(2) and exec(2) of a new process, after which the shell would check their exit status. In modern Unix shells (such as bash(1)) these are built-in commands, which makes their frequent use in scripts a lot more efficient. Why not give up this {{{if}}} template craziness and implement a basic set of programming logic operators (if, for, foreach, while, switch, ...) in the wiki syntax? Programming logic embedded in textual content is well-known from languages like PHP. -- Lars Aronsson (lars(a)aronsson.se) Aronsson Datateknik - http://aronsson.se

-----BEGIN PGP SIGNED MESSAGE----- Moin, On Wednesday 14 December 2005 15:36, Phil Boswell wrote: Exactly. This would replicate the "macro-in-document" scenario, and we all know what that leads to... May I remind everyone wanting programming logic in text documents (aka wiki pages) on this little gem: http://namb.la/popular/tech.html You have been warned. Tels - -- Signed on Sun Dec 18 11:23:52 2005 with key 0x93B84C15. Visit my photo gallery at http://bloodgate.com/photos/ PGP key on http://bloodgate.com/tels.asc or per email. "One man in a thousand is a leader of men, the other 999 follow women" -- Groucho Marx

"Lars Aronsson" <lars(a)aronsson.se> wrote in message news:Pine.LNX.4.61.0512141434370.22021@sara.aronsson.se See [[m:User:AzaToth/Logic]] which is http://meta.wikimedia.org/wiki/User:AzaToth/Logic Many thanks to Carl (aka AzaToth)! -- Adrian [[en:User:Adrian Buehlmann]]

"Ævar Arnfjörð Bjarmason" <avarab(a)gmail.com> wrote in message news:51dd1af80512122254p24be0d0aq1f3f4595c365b13b@mail.gmail.com... Sorry: given the current circumstances, nesting is not negotiable :-) What would be the ideal first step would be if someone could simply implement the functionality of the {{if}} or {{qif}} template in wikicode. This would simply test whether a supplied argument is blank or non-blank and thereby choose one of two options to transclude. We already have the {{fullurl:pagename|actionstring}} and {{localurl:pagename|actionstring}} operators. It's not a huge leap to {{if:test|thenstring|elsestring}} is it? -- Phil [[en:User:Phil Boswell]]