A shorthand for Object.defineProperty?

Axel Rauschmayer axel at rauschma.de
Mon Jun 20 16:56:26 PDT 2011


>> I meant: One can already write methods (functions with dynamic |this|) in a very concise manner, thanks for Allen’s object literal extensions. Then you have to ask: Do we really need the dynamic this arrow ->, or can we make do with just the lexical this arrow =>.
> 
> We do not propose to cripple the shorter syntax. The dynamic-this use-cases for functions are at least as common as "var self=this;... function(){... self...}" use-cases for lexical this, or roughly about the same (in my experience -- anyone have data?).


Are functions that depend on dynamic |this| ever *not* methods? Wouldn’t you always want to use an object literal for methods, especially if some features (such as |super|) depend on it?

Isn’t it then a case of
        { foo: (x) -> { ... } }
versus
        { foo(x) { ... } }

On the other hand, if the ability to omit returns can only be got via arrow->functions then I can see why you would want to keep them for methods. But even implicit returns seem to matter most in non-method settings (e.g. if a function is the argument of a function).

Maybe I just like the distinction introduced by block lambdas too much:
- dynamic this --> existing functions and methods
- lexical this --> new, more compact construct, mainly used as the argument of functions and methods.

This distinction works well as a rule of thumb and keeps things easy to explain.

-- 
Dr. Axel Rauschmayer

axel at rauschma.de
twitter.com/rauschma

home: rauschma.de
blog: 2ality.com





More information about the es-discuss mailing list