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JavaScript signature notation
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document generic objects #42

Closed Raynos closed 8 years ago

Raynos commented 9 years ago

Added an informal section to the README showing concrete examples for how to express generic objects using jsig.

This fixes #40

cc @Matt-Esch @jden

junosuarez commented 9 years ago

I commented in-line. @matt-esch, could you please add a use case? Most useful would be a code snipped you are trying to describe that requires this.

junosuarez commented 9 years ago

@Raynos good point about ES6 symbols. We'll also need a way to spec symbols (is there a customary notation for it yet?).

This seems to be handling the object-as-dictionary use case, which in languages with stronger collection types is often annotated Dictionary<TKey, TValue> as shown here.

Raynos commented 9 years ago

@jden correct, I think of Object<S <: String, T <: Any> as a generic dictionary in javascript.

Until ES6 lands with Map we will not have an alternative, and even then it will take a long time for Map to become idiomatic. Note that Object is like Map except there is restriction on the Key type to be a subtype of String.