Thx for the info and code. I can see "my $s =shift;" will take the first parameter passed to sun s_in_a; but I am not clear about @_ in "foreach (@_)", does @_ mean the array you pass in? Is it necessary to pass array by reference then dereferrence it? Thx, I appreciate it.

In reply to Re^2: boolean IN(); function in perl like by Frank John
in thread boolean IN(); function in perl like by Frank John

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