See perlsub. $ means a scalar value, and

A semicolon (;) separates mandatory arguments from optional arguments.

So, sub r($$$;$) means: r is a subroutine prototyped to take at least 3, and at most 4, scalar arguments.

Hope that helps,

Athanasius <°(((>< contra mundum

In reply to Re^3: getting ancestors of element by Athanasius
in thread getting ancestors of element by jccunning

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