TSConfig

In some cases where no type annotations are present, TypeScript will fall back to a type of any for a variable when it cannot infer the type.

This can cause some errors to be missed, for example:

ts
function fn(s) {
  // No error?
  console.log(s.subtr(3));
}
fn(42);Try

Turning on noImplicitAny however TypeScript will issue an error whenever it would have inferred any:

ts
function fn(s) {
Parameter 's' implicitly has an 'any' type.7006Parameter 's' implicitly has an 'any' type.
  console.log(s.subtr(3));
}Try