map is *greedy* and thus eats argument 4 ie the digit 1. There is a good chance you have no cgi param '1' so this becomes undef.
perldoc CGI:
If the parameter does not exist at all, then param() will return undef in a scalar context, and the empty list in a list context.
so the 1 will not become undef, it will vanish entirely.

In reply to Re^2: List context with map by ysth
in thread List context with map by abaxaba

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