I definitely understand your concern about potentially missing edge cases, and having that cause problems in the future. That's why I've been trying to make new language features disabled by default so that folks need to knowingly opt in.
In my opinion, we should have left abstract classes and private constructors disabled by default for a while, until more people could give them a try. These features haven't even been included in an official release yet. While I have a pretty good set of unit tests for each one, I'm sure that there are still some edge cases that I'll need to address in the future. - Josh On 2019/06/14 17:39:53, Alex Harui <[email protected]> wrote: > IMO, it will be a significant amount of work to provide new syntax around > typed collections to ActionScript. I cannot help here because I am not a > language expert. Having interacted briefly with the ActionScript language > team, I am certain I do not have the skills to help here and am concerned > that we'll miss something and be sorry later. > > So, as long as folks are aware of that and still want to go forward, I'm not > going to stand in their way. I am going to suggest easier ways that might > save some time because I think there are bigger fish to fry with the limited > folks we have contributing to Royale. I'd rather see a quick way of allowing > folks to use TypedArrays to see how useful/important it is and then see if we > can make Royale successful and recruit someone with language design > experience. > > IOW, creating the general case implementation starting now may not be in the > best interests of the project. I would rather we make migrating Flex code > easier/faster, and those folks may not have time to consider changing their > code to switch to TypedArrays. > > Just from some quick thinking, I would say that getting the parser to handle > some new syntax is only 25% of the work. Another 10% is in getting the > output right for JS, but the remaining 65% is handling semantics, ambiguity, > and output to other runtimes. > > Also, since Array is "final", I think it would be more work to support > Array.<int> than TypedArray.<int>. And probably even easier just to support > the exact same classnames and APIs that JavaScript supports today. Is there > some reason that Uint8Array doesn't work today? > > I'd prefer that we take the time to find an expert to help us really think > through how we will implement generics in general in AS someday, and handle > Typed Arrays as an initial implementation on that path so we don't later go > "oh crap, if we hadn't picked this particular syntax for typed arrays, our > generics support would be so much simpler!". I just know I cannot help here, > but I caution against just copying what Java or Typescript does. I think > there are patterns in ActionScript that are different from Java and TS that > might factor in. > > So, go for it if you want, but please consider future ramifications. > > -Alex > > On 6/12/19, 5:20 PM, "Greg Dove" <[email protected]> wrote: > > Alex, javascript TypeArrays are fixed length at construction, so I really > don't think that can work in general case for drop-in substitution of > numeric Vector without some sort of wrapper class that supports swapping > things out. > I really think that dedicated 'fast' numeric collection types will likely > need their own cross-target classes. > It would work for a Vector that has a fixed = true constructor arg and > then > never changes its 'fixed' status (and therefore never changes its length > also) and also only uses index access and assignments (no push, pop etc), > but it's a pretty restrictive scenario. I did look at this already. > It might also be possible to map default Vector numeric types to 'faster' > versions for the 3 types, as an opt-in to the default implementation's > approach. I do plan to work on/investigate this later this month, because > I > am keen to see performance-oriented options here too. But I was thinking > they would likely be separate, dedicated classes. > > > On Thu, Jun 13, 2019 at 11:27 AM Alex Harui <[email protected]> > wrote: > > > FWIW, I would expect any syntax changes to be a significant amount of > work > > especially where the BURM does the semantic checks. New BURM patterns > are > > probably required. Or maybe it is time to get the BURM out of the > > semantic-check business for JS (and maybe SWF) output and figure out > how to > > do the semantic checks from the JS AST walk. > > > > Did you out finding a way to indicate that some Vector.<int> should be > > implemented as a TypedArray? > > > > -Alex > > > > On 6/12/19, 3:18 PM, "Josh Tynjala" <[email protected]> wrote: > > > > I plan to start out by supporting Array.<T> syntax, similar to > > Vector.<T>. Like you said, there are advantages to using the same syntax > > for all typed collections. > > > > Later, I'll see if I can figure out how to add T[] syntax as an > > alternative, since Harbs seems to like that better. > > > > - Josh > > > > On 2019/06/12 20:14:50, Greg Dove <[email protected]> wrote: > > > Hey Josh, > > > > > > Thanks for looking into that, I figured it could be a bit tricky! > > Good luck > > > with it. > > > I think you and Harbs were maybe leaning to towards Number[] and > > String[] > > > type declarations. I don't mind either way, but perhaps the Array. > > with > > > angle brackets approach that is used for Vectors could make it > > easier to > > > swap between typed Array and Vector if people consider refactoring > > (and > > > whatever IDE they're using won't support more automated changes). > > OTOH, the > > > first approach is definitely easier to type. You probably already > > thought > > > those things through though, I guess. > > > > > > If you end up with a remote branch for your work on this at some > > point and > > > want someone to help with testing or anything like that, I'm in, > > just let > > > me know. > > > > > > > > > On Thu, Jun 13, 2019 at 2:26 AM Josh Tynjala > <[email protected]> > > wrote: > > > > > > > > I think your other proposal with Josh for the typed Arrays and > > their > > > > greater compile-time safety will be a better fit for many cases > as > > well, so > > > > I hope that happens. > > > > > > > > I started working on typed arrays this week. It may be a while > > before I > > > > can merge, though. It's definitely more complex than private > > constructors > > > > and abstract classes. > > > > > > > > - Josh > > > > > > > > On 2019/06/12 04:21:18, Greg Dove <[email protected]> wrote: > > > > > Hi Harbs - just in reply to your specific questions: > > > > > As I mentioned elsewhere it is easy to have full speed index > > access and > > > > > also full speed pop() and unshift() methods > > > > > If you switch off the first 3 settings I outlined in the post > > titled > > > > > 'Language/Reflection improvements details' you will have that. > > Those > > > > > settings are switchable locally with doc directives as well. I > > will do a > > > > > full write-up this coming weekend for docs. Hopefully I can > > harvest a lot > > > > > of what I already wrote elsewhere for that. > > > > > BTW I switched TLF to use the legacy Vector-as-Array approach > by > > > > default, I > > > > > am not sure what you want there, you could undo that if you > > prefer. > > > > > > > > > > Beyond the above mentioned approaches for (mainly index level) > > > > > optimization, I have a preference for two more approaches, but > > I'd rather > > > > > limit the overall number of options to be what people > definitely > > need > > > > > instead of adding too many options (which could create > > confusion). I > > > > think > > > > > your other proposal with Josh for the typed Arrays and their > > greater > > > > > compile-time safety will be a better fit for many cases as > well, > > so I > > > > hope > > > > > that happens. If I have time to help out in any way with > that, I > > would be > > > > > happy to do so as well, because it sounds like something I > would > > use a > > > > lot. > > > > > Anyhow, I do want to support more optimizations with this > > implementation. > > > > > Can you say what your main concerns would be for optimization? > > Is it > > > > mainly > > > > > for 'push' (and unshift) ? Those would be mine... > > > > > > > > > > I would personally like to see the following: > > > > > > > > > > 1. A global optimization setting that affects all instances in > > all code > > > > > including pre-built library code. This would avoid certain > > runtime checks > > > > > and would also result in a lighter implementation. This is > > something the > > > > > final application developer decides, not anything dictated by > a > > library > > > > > developer (but a library developer could advertise their > public > > swc as > > > > > being compatible/safe with this type of optimization). This > > approach > > > > could > > > > > include perhaps 2 levels: one to remove any code paths related > > to fixed > > > > > length Vectors (which I think you said you never used) for > > example. Then > > > > > another possibly removing all element level type-checking as > > another > > > > level. > > > > > Adding this should not be too difficult I think and would be > > determined > > > > via > > > > > a goog define (which might be driven by a compiler setting, I > > did not > > > > look > > > > > at how easy this is yet). The thing I like about this approach > > is that it > > > > > is not 'baked-in' to any instance and the application > developer > > makes the > > > > > ultimate decision and owns the associated risk (as opposed to > > having it > > > > > imposed on them by a library developer, for example). I think > > the removal > > > > > of support for 'fixed' Vectors could probably be made to > generate > > > > > (debug-only) errors if there is code that runs that sets fixed > > to true on > > > > > any Vector instance - to provide some reassurance of no side > > effects > > > > when > > > > > choosing this option. > > > > > > > > > > 2. Compilation scoped optimizations. > > > > > By 'compilation-scoped' I mean configurable in the same way as > > the > > > > > vector-index-check suppression: An over-arching config setting > > for the > > > > > current compilation that can be overridden locally with doc > > comment > > > > > directives. This affects code sites (or all current > compilation > > scope if > > > > > set in the config) and not specific instances. I would hope > this > > might be > > > > > the only other 'Vector' specific config option like this, > simply > > to avoid > > > > > confusion with too many options. > > > > > So I personally think the important things here are the push > and > > unshift > > > > > methods, because they're the ones that are also most often > used > > in loops > > > > > when index level access or assignment is not being used (in > the > > loop). > > > > But > > > > > I'm keen to hear more about what people want in case it's > > different to > > > > how > > > > > I think. And I will add support for what best represents the > > needs of the > > > > > community. While index level access is best for large loops > > (just as it > > > > is > > > > > for 'Array'), push could be preferred in small loops because > it > > does not > > > > > require a 'get' for length to establish the upper bound of the > > loop or > > > > the > > > > > next acceptable index to set (for non-fixed Vectors). The > > optimization > > > > for > > > > > push in this case would be to bypass runtime typechecking and > > just do a > > > > > regular Array.push into the underlying Vector representation, > > which is > > > > > still actually an Array in terms of how javascript sees it. > > Adding this > > > > > option is easy also, but rather than just forging ahead with > it, > > I am > > > > keen > > > > > to get input from others first. > > > > > > > > > > I consider that specific instance level optimizations (in > > general) are > > > > > 'dangerous' because even if the code is 'safe' when it is > > originally > > > > > written, subsequent changes to the overall codebase (possibly > by > > > > different > > > > > developers) can mean that an instance ends up elsewhere in > code > > where it > > > > > behaves differently from other instances of the same type. > > Code-site > > > > > optimizations could also create an unusual internal state for > an > > > > instance, > > > > > but most often they should not, because the code site where > the > > > > > optimization is used should be validated in terms of the > > optimization by > > > > > its original developer (e.g. no runtime type checking at a > > particular > > > > usage > > > > > site because it is never needed in the context of that code, > for > > example) > > > > > and the behavior of the same instance elsewhere should be much > > less of a > > > > > risk. > > > > > > > > > > More feedback from you or anyone else is definitely welcome > for > > what they > > > > > want to see for optimization options of the implementation. > I'm > > sure I > > > > can > > > > > still find more ways to improve the implementation for speed > as > > it is now > > > > > as well, I can think of a one thing I want to investigate > > further. > > > > > -Greg > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Jun 12, 2019 at 1:54 AM Harbs <[email protected]> > > wrote: > > > > > > > > > > > Practical question for me is: How do we disable to Vector > > runtime > > > > > > checking? I was having trouble following the full > discussion. > > My > > > > > > understanding was that there’s a compiler flag, but I’m not > > sure what > > > > it is. > > > > > > > > > > > > > On Jun 11, 2019, at 7:10 AM, Yishay Weiss < > > [email protected]> > > > > > > wrote: > > > > > > > > > > > > > > Language.js:868 [1] is > > > > > > > > > > > > > > if (elementType.indexOf('Vector.<') == 0) { > > > > > > > > > > > > > > > > > > > > > > > > > > > > ________________________________ > > > > > > > From: Yishay Weiss <[email protected]> > > > > > > > Sent: Tuesday, June 11, 2019 2:07:36 PM > > > > > > > To: [email protected] > > > > > > > Subject: Problem with Vectors > > > > > > > > > > > > > > Hi Greg, > > > > > > > > > > > > > > I just updated Royale and I’m seeing that in our class > > FontLoader > > > > > > > > > > > > > > private var _fonts:Vector.<Font> = new Vector.<Font>(); > > > > > > > > > > > > > > gets transpiled to > > > > > > > > > > > > > > this.com_printui_text_engine_FontLoader__fonts = > > > > > > org.apache.royale.utils.Language.Vector(); > > > > > > > > > > > > > > Notice how the type isn’t given in Vector’s constructor. > This > > > > results in > > > > > > a runtime error [1]. Any ideas? > > > > > > > > > > > > > > [1] > > > > > > > > > > > > > > TypeError: Cannot read property 'indexOf' of null > > > > > > > Watch > > > > > > > Call Stack > > > > > > > > > org.apache.royale.utils.Language.VectorSupport.vectorElementCoercion > > > > > > > Language.js:868 > > > > > > > org.apache.royale.utils.Language.synthVector > > > > > > > Language.js:642 > > > > > > > org.apache.royale.utils.Language.Vector > > > > > > > Language.js:685 > > > > > > > com.printui.text.engine.FontLoader > > > > > > > FontLoader.js:24 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
