use Symbol;
$sym = gensym; open($sym, "filename"); $_ = <$sym>; # etc.
ungensym $sym; # no effect
print qualify("x"), "\n"; # "Test::x" print qualify("x", "FOO"), "\n" # "FOO::x" print qualify("BAR::x"), "\n"; # "BAR::x" print qualify("BAR::x", "FOO"), "\n"; # "BAR::x" print qualify("STDOUT", "FOO"), "\n"; # "main::STDOUT" (global) print qualify(\*x), "\n"; # returns \*x print qualify(\*x, "FOO"), "\n"; # returns \*x
use strict refs; print { qualify_to_ref $fh } "foo!\n"; $ref = qualify_to_ref $name, $pkg;
use Symbol qw(delete_package); delete_package('Foo::Bar'); print "deleted\n" unless exists $Foo::{'Bar::'};
For backward compatibility with older implementations that didn't support anonymous globs, Symbol::ungensym is also provided. But it doesn't do anything.
Symbol::qualify turns unqualified symbol names into qualified variable names (e.g. ``myvar'' -> ``MyPackage::myvar"). If it is given a second parameter, qualify uses it as the default package; otherwise, it uses the package of its caller. Regardless, global variable names (e.g. ``STDOUT'', ``ENV'', ``SIG") are always qualfied with ``main::''.
Qualification applies only to symbol names (strings). References are left unchanged under the assumption that they are glob references, which are qualified by their nature.
Symbol::qualify_to_ref is just like Symbol::qualify except that it returns a glob ref rather than a symbol name, so you can use the result even if use strict 'refs' is in effect.
Symbol::delete_package wipes out a whole package namespace. Note this routine is not exported by default---you may want to import it explicitly.