TypeScript debuted as a beta programming language on October 1, 2012, and since then has gone through many versions that steadily improved its capabilities.
It also can be installed through Visual Studio 2017.
The upgrade also is slated to support both the JSX fragment syntax and properties named with const- declared symbols.
In strict mode, any function type that does not originate from a method has its parameters compared “contravariantly,” said Microsoft’s Daniel Rosenwasser, program manager for TypeScript.
What’s new in TypeScript 2.4
Released in June 2017, Version 2.4 of TypeScript offers improved load times with the addition of a dynamic import expressions capability.