I have two functions, function A and function B.

The result of Function B is one of the parameters that is passed to function A. Function A then does something with this and returns the result.

The problem I have is that I'm not sure what Function B is going to return. It may return a scalar, it may return an array or it may return a hash. It may even be a reference to one of these.

Therefore, this makes it very difficult to code Function A when you're not sure what it's going to get. Obviously the correct way would be always to pass Function A a reference to whatever Function B returned, but how can I create the reference to it when I don't know what it's going to be?

Function A can easily detect references and scalars (if it only got one value), but if it gets more than one value, then it could either be an array or a hash, and I can't see how it could tell the difference unless it was a reference.

As an extra bonus, the call to Function A, with whatever is being passed to it (the result of Function B and whatever other parameters), must be a single line.

Challenge extended.

In reply to Auto-detecting returned or passed variable type by richard5mith

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