In perlboot, an intro to OO in Perl, it is discussed in The extra parameter of method invocation.

Update: To answer your updated question, the package name or blessed object are passed in a method invocation whenever you use the The Arrow Operator to invoke a package method. So Node->new() will pass "Node" and new(), Node::new() or $code_ref->() would not.

In reply to Re^5: Would someone mind helping me understand this Perl OO code? by kennethk
in thread Would someone mind helping me understand this Perl OO code? by romandas

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