Awesome, did not know this.

TypeScript type inference is minimal though and doesn't go very far. It falls back to "any" very quickly (and if you use the noImplicitAny option, then you have to type almost everything).

It does a decent enough job at return types, but not a whole lot beyond that.

Do you have a use case where something would be correctly inferred in Flow but not in TS?

The classic example is:

  function double(x) {
    return x * 2;
  }
  const result = double("foo");

Which passes in TS, but fails in Flow. In TS, the 'x' parameter to the double function is inferred as Any.