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Re: Object.create(canvas.getContext())

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Jan Bruns wrote:

> Thomas 'PointedEars' Lahn:
>> Jan Bruns wrote:
>>> this.define_method = function(nam,cobj,cfun){
>>> 
>>>  this[nam] = function() { return cfun.apply(cobj,arguments); };
>>> 
>>> };
>>> 
>>> this.inherit_methods = function(o) {
>>> 
>>>   for (var i in o) { if (typeof(o[i])=="function") {
>>> 
>>>     this.define_method(i,o,o[i]);
>>> 
>>> };};};
>>> 
>>> 
>>> this.inherit_methods(gl);
>>> 
>>> Looks much more human readable to me.
>  
>> YMMV.  But your code is also much more error-prone
> 
> Well, it comes with useful flexibility.

You misunderstand.  I had not criticized your approach as I understood it 
then, but your implementation of it.
 
> So it'll simply be best to load the extension with:
> 
>   var e = gl.getExtension(some_name);
>   gl.define_method("someMethod",e,e.someMethod_suffix);

Probably not.  ISTM now that you are trying to augment a host object, which 
is a recipe for disaster.

>> (and lacks code style).
> 
> Style? My newsreader is broken (I think). Somehow linebreaks get lost
> somewhere, probably to get some format-flowed styling.

Perhaps.
 
>> For example, there is a reason why I enclosed the host object property
>> access in a “try” block.
> 
> What is that reason? Does "typeof" throw on any enumerated property
> anywhere?

If you would have tried, you would have seen that

  typeof Object.getPrototypeOf(webGLcontext)[name] == "function"

throws “TypeError: Illegal invocation” for the _enumerable_ properties where

  name === "canvas"

  name === "drawingBufferWidth"

and

  name === "drawingBufferHeight"

in Chrome 57 (navigator.userAgent === "Mozilla/5.0 (X11; Linux x86_64) 
AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.98 Safari/537.36").

You need to realize that those are *host* objects, and all bets are off.

-- 
PointedEars
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<https://github.com/PointedEars> | <http://PointedEars.de/wsvn/>
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Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-12 10:09 +0000
  Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-12 17:42 +0100
    Re: Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-14 11:48 +0000
      Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-15 02:32 +0100
        Re: Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-17 20:25 +0000
          Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-19 05:48 +0100
            Re: Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-19 21:39 +0000
              Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-19 23:34 +0100
                Re: Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-20 14:47 +0000
                Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-21 04:07 +0100
                Re: Object.create(canvas.getContext()) Jan Bruns <ebay@abnuto.de> - 2017-11-21 16:23 +0000
                Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-22 04:12 +0100
  Re: Object.create(canvas.getContext()) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-11-12 18:45 +0100

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