What is // doing in the above code?

// in this case is the Logical Defined Or (as opposed to the empty regular expression, for example in "$foo =~ //;"). The expression $data{$key}{$file} // 0 is the same as defined($data{$key}{$file}) ? $data{$key}{$file} : 0

In reply to Re^3: open input files once by haukex
in thread open input files once by v15

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