// is the defined or operator. || is the or operator. // and //= were added in in 5.10 as a shortcut for something along the lines of $var = defined $var ? $var : $default_value;

$var //= $default_value; is much prettier IMHO. I'm fairly certain // and || short-circuit in the same exact way. It's easy enough to test.

In reply to Re^3: Scope Issue by AR
in thread Scope Issue by MKJ747

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