polyfill-symbol-metadata

A polyfill for Symbol.metadata to support @tc39/proposal-decorator-metadata

These packages are only temporary for stage 3 of decorators until TC39 officially supports decorators.

Usage

import "polyfill-symbol-metadata";

function meta(key, value) {
  return (_, context) => {
    context.metadata[key] = value;
  };
}

@meta("a", "x")
class C {
  @meta("b", "y")
  m() {}
}

C[Symbol.metadata].a; // 'x'
C[Symbol.metadata].b; // 'y'

REF

• https://github.com/tc39/proposal-decorator-metadata/issues/14#issuecomment-2136289464

Relative issues

• https://github.com/denoland/deno/issues/22111