The parens around %hash are not required in this case, but it is customary to use them.

The parens around shift are necessary, as you can easily prove if you remove them. I believe perl thinks that shift is the name of a variable, instead of the built-in function. Using strict, I get this compile error: 

Global symbol "%shift" requires explicit package name at 
BEGIN not safe after errors--compilation aborted at

[download]

diagnostics gives even more info.

In reply to Re: hash to sub by toolic
in thread hash to sub by Anonymous Monk

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