You are welcome to try and see how many cache hits it gets. I think in renderers, we ask once per renderer. I'm not sure there is a faster way to do the first lookup of "is", but for "has" we could change the lookup and save time.
On 1/15/20, 10:38 PM, "Greg Dove" <[email protected]> wrote: For the 'something is ISomeInterface' I had wondered in the past if these types of lookups could be incrementally cached on the 'is' target (after first lookup), that might make sense for interfaces, which are the deepest checks I think? caching result (could optionally create the Map) ISomeInterface['implMap'].set(something.constructor, isResult ) then earlier in the interface checks, it could do something like: if (ISomeInterface['implMap'] && ISomeInterface['implMap'].has(something.constructor) ) return ISomeInterface['implMap'].get(something.constructor) I realize its extra code, but it should be quite a bit faster over time I think. On Thu, Jan 16, 2020 at 7:20 PM Alex Harui <[email protected]> wrote: > Hi, > > Several different threads have brought up issues with sharing code between > component sets. Other threads have offered different and clever ways to > do various things like how MXML is applied to a component. Meanwhile, over > in MX emulation, I was starting to copy some code from Basic to MXRoyale to > get the various MX components to be valid item renderers. MXRoyale is > using Basic's item renderer architecture which is better encapsulated: the > renderer draws its hovered and selected state. In Flex, the List draws > over the renderer, which makes it hard to customize the way the renderer > will look when hovered and selected. > > It finally occurred to me that one of the reasons we end up copying code > is because we are still using too many "is" checks instead of "has" > checks. I'm not even sure we have any "has" checks in the Royale > framework. I was afraid of the overhead of a "has" check, but I'm starting > to change my mind because: > > 1) The "is" check actually runs a fair amount of code, especially for > (comp is ISomeInterface) > 2) The length of bead arrays don't seem too long. > > A "has" check calls getBeadByType(ISomeInterface), so it actually will run > the (bead is ISomeInterface) on potentially the entire strand array/vector, > although we could speed that up by annotating beads or keeping track of > what is on the strand. But the code sharing/reuse potential of this > pattern seems significant to me. > > For example, it could change how hard it is to make a component usable as > a top tag in MXML. Instead of the component having to implement certain > methods, the component could have a bead installed and the > MXMLDataInterpreter could talk to that bead instead of the component. > > In the case of the item renderers, instead of testing if the renderer "is" > ISelectableLIstItemRenderer, it could ask if the created widget "has" an > ISelectableLIstItemRenderer bead and the logic in that bead can be reused > in both Basic and MXRoyale without being copied. > > Some code, like Container overrides of addElement probably can't be > refactored into a "has". But I wonder how many other things could. I'm > not sure I would move everything that could be moved into a shared bead. > We'd have to think about the overhead on small components and apps. But > for MXML support and Item Renderer support, it seems to make sense. > > Anyway, I will look into refactoring the item renderer code in a few days > unless feedback indicates otherwise. Bugs like #676 and #681 inspired this > post. > > Of course, I could be wrong... > -Alex > >
