I'm trying to use the solution posted here to create a GUID-type string in my angular4/TypeScript web app. Here is the function I'm writing: function uuidv4() { return ([1e7]+-1e3+-4e3+-8e3+-1e11).replace(/[018]/g, c => (c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16) ) } console.log(uuidv4()) TypeScript is giving me the following error: Operator '+' cannot be applied to types 'number[]' and '-1000'. What do I need to change to make this TS compatible? Thanks! Continue reading...