4 ms·

But that's essentially a table lookup, not a vtable lookup, right? Dynamic dispatch implies that you dispatch based on the class of the receiver. For instance,

• lalaithion 6y ago
  let Point3 = (x, y, z) => { let parent = Point(x, y); let self = (message, args=null) => { switch (message) { // getters case 'z': return z // some operations // (immutable, but that's not required) case 'toString': return `Point(x=${x}, y=${y}, z=${z})`; case 'move': let [dx, dy, dz] = args; // use our getters return Point(self('x')+dx, self('y')+dy, self('z')+dz); // let's get DRY! case 'plus': let [other] = args; return self('move', other('x'), other('y'), other('z')); default: parent(msg, args) } }; return self; };
• uryga 6y ago
  maybe "extremely late binding" would be more appropriate? it's true that usually "dynamic dispatch" means a vtable, but i think this is dynamic dispatch in spirit - in fact "dispatching" messages to implementations is pretty much the only thing a closure-object does :) i chose to write the impls inline, so they're p much impossible to reuse, but that's not required. > you can't have a Point3 value that uses Point's implementation of 'x' and its own implementation of 'toString' under this example. you can't do much of anything under this this example! i didn't think a whole object system would fit in a HN comment, i intended it to be minimal :)