You can see if a package exists by checking if its symbol table is defined. 

package Foo;
$a = 1;
package main;
print "foo\n" if defined %Foo::;
print "bar\n" if defined %Bar::;

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Note that the symbol table won't be defined until you put a symbol in it; a mere package declaration doesn't seem to do it.

In reply to Re: multiple package in one file by friedo
in thread multiple packages in one file by jeanluca

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