using Typescript callback style error handling

getData(someParameter, function(err: Error | null, resultA: ResultA) {
  if(err !== null) {
    // do something like calling the given callback function and pass the error
    getMoreData(resultA, function(err: Error | null, resultB: ResultB) {
      if(err !== null) {
        // do something like calling the given callback function and pass the error
        getMoreData(resultB, function(resultC: ResultC) {
          getMoreData(resultC, function(err: Error | null, d: ResultD) {
            if(err !== null) {
              // you get the idea?
            }
          })
        });
      }
    });
  }
});

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