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Symbol(3pm)			 Perl Programmers Reference Guide		      Symbol(3pm)

       Symbol - manipulate Perl symbols and their names

	   use Symbol;

	   $sym = gensym;
	   open($sym, "filename");
	   $_ = <$sym>;
	   # etc.

	   ungensym $sym;      # no effect

	   # replace *FOO{IO} handle but not $FOO, %FOO, etc.
	   *FOO = geniosym;

	   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);
	   print "deleted\n" unless exists $Foo::{'Bar::'};

       "Symbol::gensym" creates an anonymous glob and returns a reference to it.  Such a glob
       reference can be used as a file or directory handle.

       For backward compatibility with older implementations that didn't support anonymous globs,
       "Symbol::ungensym" is also provided.  But it doesn't do anything.

       "Symbol::geniosym" creates an anonymous IO handle.  This can be assigned into an existing
       glob without affecting the non-IO portions of the glob.

       "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 qualified 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

       "Symbol::delete_package" wipes out a whole package namespace.  Note this routine is not
       exported by default--you may want to import it explicitly.

perl v5.8.0				    2002-06-01				      Symbol(3pm)
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