TypeScript 4.0 Released: Complete Overview

TypeScript 4.0 is here. Major features include variadic tuples, class property inference, and short-circuit assignment.

Short-Circuit Assignment

x ||= y;  // x = x || y
x &&= y;  // x = x && y  
x ??= y;  // x = x ?? y

Unknown on Catch

try { ... } 
catch (e: unknown) {  // Safer than any
  if (e instanceof Error) console.log(e.message);
}

References

• TS 4.0 Release