es6 Map() doesn't compile to es5 when using Typescript
I've just started using Typescript in a project for the first time. I really want to use Map() to organize a small array of key value pairs. Unfortunately when the typescript is compiled (using gulp and gulp-typescript) to vanilla, ES5 JavaScript, Map() still exists. I need this code to work in ie9. Any advice at this stage would be greatly appreciated. Map is a part of ES6 and have nothing to do with TypeScript. If you want tot use Map in ES5 environment you should include an appropriate polyfill. My first two thoughts are: es6-map module core-js/es6/map from core-js generic ES6 polyfill