Symbol(3) Perl Programmers Reference Guide Symbol(3)NAMESymbol - manipulate Perl symbols and their names
SYNOPSIS
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 Symbolqw(delete_package);
delete_package('Foo::Bar');
print "deleted\n" unless exists $Foo::{'Bar::'};
DESCRIPTION
"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::qualify" turns unqualified symbol names into
qualified variable names (e.g. "myvar" -> "MyPack
age::myvar"). If it is given a second parameter, "qual
ify" 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 effect.
"Symbol::delete_package" wipes out a whole package names
pace. Note this routine is not exported by default--you
may want to import it explicitly.
2001-02-22 perl v5.6.1 Symbol(3)
