Type assertions gives type information to typescript generally to details the type information of an any variable type.
It does not perform any special check or restructuration of data such as a type cast.
The “angle-bracket” syntax:
let someValue: any = "this is a string";
let strLength: number = (<string>someValue).length;
let someValue: any = "this is a string";
let strLength: number = (someValue as string).length;