Symbol(3) Symbol(3)
Symbol - manipulate Perl symbols and their names
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;
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" -> "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.
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Symbol(3) Symbol(3)
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