Object.assign()

Rick Waldron waldron.rick at gmail.com
Wed Oct 17 20:04:17 PDT 2012


On Wednesday, October 17, 2012 at 10:53 PM, Axel Rauschmayer wrote:
> Addendum: For example, you won’t be able to reliably use Object.assign() to mix an object with methods into a prototype object, because those methods might be non-enumerable.
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This not a silver bullet by any means. If you define that object and all of those methods haven't been explicitly set to enumerable:false, then they will all copy

Rick  
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> I think I initially misunderstood you. You think that what I’ve mentioned above is a feature, I’d argue that it is a bug.
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> On Oct 18, 2012, at 4:47 , Axel Rauschmayer <axel at rauschma.de (mailto:axel at rauschma.de)> wrote:
> > > > On Wednesday, October 17, 2012 at 10:27 PM, Axel Rauschmayer wrote:
> > > > > I’m a bit skeptical about excluding non-enumerable properties for Object.assign(). I still find enumerability a hard concept to wrap my mind around, because it pops up in unexpected places. At the moment, it mostly matters for for...in and Object.keys()/Object.getOwnPropertyNames(). Does it really make sense to increase its role in JavaScript?
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> > > It's a matter of paving the cow path of least surprise. Imagine if you tried to copy the properties and values of a plain object to an object with a null prototype and all of those properties you explicitly didn't want were now present.
> > But those won’t be copied, because only own properties will be copied. I’d be more worried about adding non-enumerable own properties to an object and those *not* being copied.
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> > --  
> > Dr. Axel Rauschmayer
> > axel at rauschma.de (mailto:axel at rauschma.de)
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> > home: rauschma.de (http://rauschma.de/)twitter: twitter.com/rauschma (http://twitter.com/rauschma)
> > blog: 2ality.com (http://2ality.com/)
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> --  
> Dr. Axel Rauschmayer
> axel at rauschma.de (mailto:axel at rauschma.de)
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> home: rauschma.de (http://rauschma.de)twitter: twitter.com/rauschma (http://twitter.com/rauschma)
> blog: 2ality.com (http://2ality.com)
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