Note this last revision brings back a bit more of Robert's version, it's more 50/50 now.
Rick On Thu, Jun 25, 2009 at 12:53 PM, Rick Waldron <waldron.r...@gmail.com>wrote: > You're right... It appears i copied the source in a bit hastily. After > re-examining, I've revised again... > > http://jsbin.com/ajoqu > > Rick > > > > > On Thu, Jun 25, 2009 at 9:37 AM, joe t. <thooke...@gmail.com> wrote: > >> >> Rick, >> Maybe i'm missing how that revision works, but it appears to me that >> your stop property doesn't actually stop the repeater. Your stop >> returns before further execution happens, but the timeout ID for the >> window still exists. >> >> What am i missing? >> -joe t. >> >> >> On Jun 24, 12:20 pm, Rick Waldron <waldron.r...@gmail.com> wrote: >> > I made a few modifications to your version, allowing repeat() to behave >> like >> > delay() with regard to arguments >> > >> > I've posted a demo here: >> > >> > http://jsbin.com/ekone >> > >> > All the output is to the firebug console... i've included fbug lite just >> in >> > case >> > >> > Rick >> > >> > On Wed, Jun 24, 2009 at 10:50 AM, Rick Waldron <waldron.r...@gmail.com >> >wrote: >> > >> > > I've subbed my implementation with your to do some use-case testing. >> I'll >> > > report back anything of interest as I go along. >> > >> > > Rick >> > >> > > On Wed, Jun 24, 2009 at 10:49 AM, Rick Waldron < >> waldron.r...@gmail.com>wrote: >> > >> > >> This is fantastic feedback - thanks! >> > >> > >> On Wed, Jun 24, 2009 at 9:55 AM, Robert Kieffer <bro...@gmail.com> >> wrote: >> > >> > >>> I can't say I'm a big fan of this. For several reasons. >> > >> > >>> First, it's just a cosmetic replacement for setInterval(myfunction >> > >>> (...).bind(), ...) which simply isn't all that bad. >> > >> > >>> Second, I'm not a fan of setInterval in general. I've seen some >> > >>> rather nasty behavior with calls queuing up if the invoked function >> > >>> takes longer than the delay to execute. In particular, this seems >> to >> > >>> be an issue if you do something like put a laptop to sleep. (But >> > >>> maybe others haven't seen this problem???) Thus, I prefer to use a >> > >>> self-invoking timeout like so: >> > >> > >>> function myFunction() { >> > >>> // do stuff ... >> > >>> // call ourselves again >> > >>> if (/*we want to continue?*/) setTimeout(myFunction, 1000) >> > >>> } >> > >> > >>> This doesn't call the function at exactly one second intervals, but >> > >>> that type of accuracy is rarely important. Instead, it guarantees >> you >> > >>> have at least one second of delay between invocations, which for >> > >>> distributing cpu load or polling (the more common cases where >> > >>> setInterval might be used), is more desireable. >> > >> > >>> Finally, as Joe T. points out, there should be a way of cancelling >> the >> > >>> interval that doesn't require the user to store the returned value >> > >>> (*that* is what I find most annoying, not the syntax of >> > >>> "setInterval"). >> > >> > >>> Thus, I'd suggest this instead: >> > >> > >>> Object.extend(Function.prototype, { >> > >>> repeat: function(delay) { >> > >>> // Reset state >> > >>> if (this._repeater) delete this._repeater; >> > >>> this._repeatTimeout = clearTimeout(this._repeatTimeout); >> > >> > >>> if (!delay) return; // (stop repeating if no args or delay==0) >> > >> > >>> // Create setTimeout-based invoker >> > >>> var _method = this; >> > >>> if (!this._repeater) this._repeater = function() { >> > >>> // Let _method cancel repeat by doing "return false;" >> > >>> if (_method() !== false) setTimeout(_method._repeater, >> delay); >> > >>> } >> > >> > >>> // Start repeating >> > >>> this._repeatTimeout = setTimeout(this._repeater, delay); >> > >>> }, >> > >> > >>> stopRepeating: function() { >> > >>> this.repeat(); >> > >>> } >> > >>> }); >> > >> > >>> For example: >> > >> > >>> var count = 0; >> > >>> function foo() { >> > >>> console.log(count++); >> > >>> return count < 10; // Return "false" when count >= 10 to cancel >> > >>> the repeat >> > >>> } >> > >> > >>> // Start repeating 1/sec >> > >>> foo.repeat(1000); >> > >>> //... some time later change interval to 2/sec >> > >>> foo.repeat(500); >> > >>> // ... later still stop repeating. >> > >>> foo.stopRepeating(); >> > >> > >>> As you can see, this implementation of repeat() does a lot more for >> > >>> you than simply alias'ing "setInterval": >> > >>> - It guarantees your function is only invoked by one interval >> > >>> - It makes changing the interval or cancelling it altogether >> > >>> trivial. >> > >>> - It allows you to conditionally cancel the repeat from w/in the >> > >>> function itself. >> > >> > >>> The only thing missing is the bind() behavior but, well, that's what >> > >>> bind is for. If you need to bind arguments, just bind() your >> > >>> arguments first. >> > >> > >>> On Jun 23, 8:25 am, Rick Waldron <waldron.r...@gmail.com> wrote: >> > >>> > I detest the way setInterval() looks, so I came up with this... >> have >> > >>> been >> > >>> > using it my personal JS for some time. >> > >> > >>> > Object.extend(Function.prototype, { >> > >>> > repeat: function() { >> > >>> > var __method = this, args = $A(arguments), interval = >> args.shift() >> > >>> * >> > >>> > 1000; >> > >>> > return window.setInterval(function() { >> > >>> > return __method.apply(__method, args); >> > >>> > }, interval ); >> > >>> > } >> > >> > >>> > }); >> > >> > >>> > // usage: >> > >>> > var _pollInt = 0; >> > >>> > function repetiousPollFn() { >> > >>> > console.log(_pollInt++); >> > >> > >>> > } >> > >> > >>> > repetiousPollFn.repeat(.5); >> > >> > >>> > Will, of course, repeat repetiousPollFn() every half second. >> > >> > >>> > Almost identical to .delay(), except that it returns setInterval >> > >>> instead of >> > >>> > setTimeout. One thing I intend to add is support for >> clearInterval, >> > >>> however >> > >>> > I figured I'd at least bring it up here first. I've never >> > >>> > proposed/contributed here before (i'm a lurker of the list :D ) - >> any >> > >>> > guidance is appreciated. >> > >> > >>> > Rick >> > >> > >> >> >> > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Prototype: Core" group. To post to this group, send email to prototype-core@googlegroups.com To unsubscribe from this group, send email to prototype-core-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/prototype-core?hl=en -~----------~----~----~----~------~----~------~--~---
