Contains:

• native curried matchAll
• ponyfill curried matchAll
• tests
• typescript definition
• export

Decisions/Tradeoffs:

• native "matchAll" returns an iterable type: RegExpStringIterator. This is why most of the examples look like [..."testtest".matchAll("te")], spreading the iterable into a regular Array. Creating this kind of iterator in polyfill involves symbols, generators, and other ES6 elements that should be polyfilled too, in a long and not perfect chain. So I decided to directly return the Array as a result, making some rarely used optimization of matchAll impossible.
• EcmaScript official documentation says that matchAll non global regex should throw an error (@see 21.1.3.12 in https://tc39.es/ecma262/#sec-string.prototype.matchall). Main browsers implements that behavior but node.js 12+ doesn't, so there is no test to "test this error" (except for the ponyfill that enforce the correct error).