I think you're slightly confused about what these error messages mean. If you don't declare a variable, you'll get the "requires explicit package name" error. This is triggered by use strict, not by -w.

$ perl -Mstrict -le 'print $x'
Global symbol "$x" requires explicit package name at -e line 1.
Execution of -e aborted due to compilation errors.

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The error we're dicsussing here is seen whenever you try to print a variable that contains "undef" (even if it's previously been declared). This is triggered by -w (or use warnings).

$ perl -Mstrict -w -le 'print my $x'
Use of uninitialized value in print at -e line 1.

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<http://www.dave.org.uk>

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In reply to Re: Re: The -w switch on a web application by davorg
in thread The -w switch on a web application by Heidegger

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