Example of using values as types - with type assertion

value-types.ts

const Foo = {
    aFoo: 'SomeAfoo' as 'SomeAfoo',
    bFoo: 'SomeBfoo' as 'SomeBfoo',
    cFoo: 'SomeCfoo' as 'SomeCfoo',
};

type FooValueTypes = (typeof Foo)[keyof typeof Foo];

function doStuff(value: FooValueTypes) {
}

// compiles!
doStuff('SomeAfoo');

// won't compile!
doStuff('Another string');