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Associated functions and associated constants sound so yum! That's one thing I would love to have in Flowtype. But classes seem to serve that use case well enou

by pcx 9y ago

Associated functions and associated constants sound so yum! That's one thing I would love to have in Flowtype. But classes seem to serve that use case well enough.

SideburnsOfDoom 9y ago
> Associated functions and associated constants sound so yum! In the simple (not trait) case they just seem to be the same as "public static" constants and functions in C#, java etc.
a_humean 9y ago
You get something similar to with static methods and properties on class definitions. In plain ES2017-ish class syntax: class Test { static value = 1; static someStaticMethod = () => { return 5; } } console.log(Test.value) // 1 console.log(Test.someStaticMethod()) // 5 Edit: Sorry, this actually a Stage 3 TC39 feature. Not sure if you can use it with flowtype (I think you can), but you might be able to if you enable babel with stage-3 features: https://github.com/tc39/proposal-class-fields https://github.com/tc39/proposal-class-fields You don't actually need this fancy class syntax anyway. You can just define a class and then do: Test.value = 5 Test.someStaticMethod = () => { return 5; } The class stuff is just sugar over the prototype stuff anyway, and a class is just a constructor function object with a prototype chain.
- pcx 9y ago
  Yeah, either way it is objects. Traits feel so much more flexible though; and more natural a layer over JS object-orientedness. It also makes it a pain that there are some important semantics missing while using classes in JS. Someitmes Java feels much better.
  - akatechis 9y ago
    The real problem is that ES classes map onto a paradigm of prototypal inheritance rather than traditional inheritance (as in Java). The discrepancies between the two cause a leaky abstraction, like how a class still has a prototype chain, for example.
- fish_fan 9y ago
  Note, I think in spite of being in stage 3 the syntax and obvious cases seem to be largely unlikely to change. It certainly improves react quite a bit: you can define the proptypes and default values inside the class rather than after.

by pcx 9y ago

Associated functions and associated constants sound so yum! That's one thing I would love to have in Flowtype. But classes seem to serve that use case well enough.

SideburnsOfDoom 9y ago

> Associated functions and associated constants sound so yum! In the simple (not trait) case they just seem to be the same as "public static" constants and functions in C#, java etc.

a_humean 9y ago

You get something similar to with static methods and properties on class definitions. In plain ES2017-ish class syntax: class Test { static value = 1; static someStaticMethod = () => { return 5; } } console.log(Test.value) // 1 console.log(Test.someStaticMethod()) // 5 Edit: Sorry, this actually a Stage 3 TC39 feature. Not sure if you can use it with flowtype (I think you can), but you might be able to if you enable babel with stage-3 features: https://github.com/tc39/proposal-class-fields https://github.com/tc39/proposal-class-fields You don't actually need this fancy class syntax anyway. You can just define a class and then do: Test.value = 5 Test.someStaticMethod = () => { return 5; } The class stuff is just sugar over the prototype stuff anyway, and a class is just a constructor function object with a prototype chain.

pcx 9y ago
Yeah, either way it is objects. Traits feel so much more flexible though; and more natural a layer over JS object-orientedness. It also makes it a pain that there are some important semantics missing while using classes in JS. Someitmes Java feels much better.
- akatechis 9y ago
  The real problem is that ES classes map onto a paradigm of prototypal inheritance rather than traditional inheritance (as in Java). The discrepancies between the two cause a leaky abstraction, like how a class still has a prototype chain, for example.
fish_fan 9y ago
Note, I think in spite of being in stage 3 the syntax and obvious cases seem to be largely unlikely to change. It certainly improves react quite a bit: you can define the proptypes and default values inside the class rather than after.