Discuss
  • Symbol description inference

Symbol description inference

# Shahar Or (9 years ago)

So, we have function name inference, like

const funcs = { foo: () => {} }

funcs.foo.name === 'foo' // true

and this inference also works similarly with const foo = () => {} and

such.

So, how about Symbol description inference, like:

const symbols: {
  foo: Symbol(),
  bar: Symbol()
}
symbols.foo // Symbol(foo)
symbols.bar // Symbol(bar)

and const foo = Symbol() and such?

Here is my real use case: yarom-and-shahar/cyclejs-shooter/blob/feaaf0ecd7620832b4bff90ab0f701d51ddcf3ff/src/ui-from-state/index.test.js#L22

# Allen Wirfs-Brock (9 years ago)

Function name inferencing is possible because function definitions are all syntactic special forms that can be unambiguously identified during parsing.

Symbols creation is just a function call so there is no way to reliably detect it. Symbol might aliased to some other name by assignment, a different value other than the Symbol creation function might be assigned to the global Symbol, or some alternative declaration of Symbol might be in some at the point of use.

# Alexander Jones (9 years ago)

IMO, the real problem that needs solving is macros. Macro-based definition of a symbol could trivially reuse the name.

# Michał Wadas (9 years ago)

Actually I think symbol name interference should be left as implementation detail. So I would change 19.4.1.1 § 2 to allow implementations for custom behavior.