Angular 2 typescript invoke javascript function
You have to tell TypeScript about external (JavaScript) declarations using declare. See https://www.typescriptlang.org/docs/handbook/writing-declaration-files.html
interface MyTheme {
documentOnLoad: Function;
documentOnReady: Function;
}
declare var MYTHEME: MyTheme;
Or anonymously
declare var MYTHEME: {documentOnLoad: Function, documentOnReady: Function};