Im revising a code written in perl and I'm finding the use of "//" in different ways: tests, shift, others.

return 1 unless ($flag // 0)

return 1 unless ($flag // 1)

if $HAS_FOCUS // ''

$socket = shift // $SOCKET_CLIENT;

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I have searched and I do not find what does "//" means. In what section of the documentations is this explained

In reply to Meaning of // by hanspr

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