Exceptions? about cello HOT 3 CLOSED

I actually came here to see what was the process for making a data type such as Maybe or Either. I think Go has proven successful with its no-exceptions policy. It simply returns two values from every function that might fail.

I think that C+ should do this as well. And since it seems heavily flavored by Haskell. Either should be just the thing.

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There are a couple of things to consider with return codes in C+.

First of all is that functions cannot really return rich C+ data objects unless they are allocated on the heap. This leaves a performance overhead and also a policy overhead where the user has to free any returned data. Unfortunately this extends to tuple type objects - so returning pairs of (result, error) would be fairly troublesome.

Similar reasoning extends to some kind of "Maybe" object.

A second option is to (because C+ is not statically typed), return some singleton on error such as "None". While this is a fairly practical solution I've always hated languages which do this because it means either you simply defer errors to some weird location and make debugging difficult, or that you check the return object of every function in a paranoid way. Although this is actually what I do at the moment for functions like "at" when the index is out of bounds.

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Exceptions have been added in most recent updates.

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