Aug 2023
22m 28s
In this Hasty Treat, Scott and Wes talk about whether decorators are finally here, what the uses cases are for decorators, how to define a decorator, and what auto accessor is.
on classes
@loggged class C {} on fields
class C { @logged x = 1; } Auto Accessor
class C { accessor x = 1; } sugar for below
class C { #x = 1; // # means private get x() { return this.#x; } set x(val) { this.#x = val; } } Can be decorated and decorator can return new get and set and init functions
function logged(value, { kind, name }) { if (kind === "accessor") { let { get, set } = value; return { get() { console.log(`getting ${name}`); return get.call(this); }, set(val) { console.log(`setting ${name} to ${val}`); return set.call(this, val); }, init(initialValue) { console.log(`initializing ${name} with value ${initialValue}`); return initialValue; } }; } // ... }