OK, why is {0+$ref} faster? I can see the different semantics... $hash{$ref} converts the ref to a string, while $hash{0+$ref} converts the ref to a number and then to a string. A quick test shows that converting a ref to a number returns (no surprise) a number, probably the machine address of an underlying unique piece of data in the interpreter, the same as the hex value shown in the stringification form.

So why would the latter be faster?

—John

In reply to Re: Re: Marking an array as already seen (yes) by John M. Dlugosz
in thread Marking an array as already seen by John M. Dlugosz

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