Porting 30K lines of code from Flow to TypeScript

Re:Porting 30K lines of code from Flow to TypeScript by lhorie on Monday January 14, 2019 @06:56PM (#18907743)

My point is mostly that you can get away with explicitly typing less things in flow and still get similar levels of coverage. For example, consider this example:

    export function formatTime(time: Date) {
      return digitize(time.getHours()) + ':' + digitize(time.getMinutes());
    }
    function digitize(n) {
      return ('0' + n.toStirng()).substring(-2);
    }

Just a single type declaration is enough to let Flow catch the typo here. In TS, you'd also have to write the argument types for `digitize`. Importantly, if you wanted to explicitly add arg types for `digitize` w/ Flow, your editor can tell you what they are supposed to be.

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Re:Porting 30K lines of code from Flow to TypeScript by z3t4 on Tuesday January 15, 2019 @05:20AM (#18910101)

FLow seem to be better at inferring types. example:

    function foo(n) {
          return n*2;
    }
    
    foo("bar");

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