Exception nesting/wrapping in TypeScript

Question

Is it possible/common-practice to nest/wrap exception (cause) in TypeScript, like in Java?

try {
  // do something
} catch (e) {
  throw new MyException("Exception while doing something", e);
}

I mean it's probably not a problem to just have a custom ctor for MyException , to pass in the e arg as cause , but what about reporting (printing) the stack traces later on?

Answer 1

If you're looking for the stack trace then you can do this:

function normalizeError(e: any): Error {
    if (e instanceof Error) {
        return e;
    }

    return new Error(typeof e === "string" ? e : e.toString());
}

And then:

try {
    throw [1, "string", true];
}
catch (e) {
    e = normalizeError(e);
    console.log(e.stack);
}

Which will print something like:

Error: 1,string,true
at normalizeError (:5:12)
at :11:9

If you are targetting es6 then you can extend the Error class instead of having this normalizeError function, but if you can't target es6 then you should avoid extending native classes.