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No, it's a system that takes 1 input (anyval0) and outputs either an error OR anyval1. If any of the functions errors, it rides the "error" track back up and returns the first error that it encounters. This is fail fast method using flatmap.

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Sounds like it’s a convoluted way to implement the same kind of thing that you’d get with a traditional error throwing paradigm

What's convoluted about it? Exceptions jumping up multiple stacks and being rescued or reraised or what have you is convoluted. If you mean errors as return values then I agree, monads are more complicated than returning a simple error type.

The part you might be missing is that you're explicitly told "this function returns a value OR and error. You must handle error cases with this function". With the try/catch paradigm you never know from the function definition if that is the case.

You also know what type the error will be. No need to derive a new class from `Error` and add custom functions to extract the data from your failure case, just pass the data along.

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