You're probably familiar with the semi-special value '0 but true', which works like 0 in any arithmetic operation, yet still evaluates to true. You can also use '0e0' or other varieties.

But in this case, what I'd like is a true value that acts as the "nothing value" not just in arithmetic operations, but also in string operations. So if $x has this value, if($x) is true, but $x.$y is just $y.

One sneaky solution is control characters, like $x="\c@". That gives a true value, and printouts will look correct. But it still means that if($x.$y eq $y) will fail, and anyone who tries to use length() is going to end up very confused.

Is there a way to do this?

In reply to "" but true by Chuma

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