() = empty arguments. you can only omit the braces when you have 1 argument. 0 and 2+ require the braces. #tc39 the colon refers to flow and typescripts type a

() = empty arguments. you can only omit the braces when you have 1 argument. 0 and 2+ require the braces. #tc39 the colon refers to flow and typescripts type annotation "colon something". none-objects are lowercased