lib:attrs
See the current Perl documentation for lib:attrs.
Here is our local, out-dated (pre-5.6) version:
attrs - set/get attributes of a subroutine
sub foo { use attrs qw(locked method); ... }
@a = attrs::get(\&foo);
This module lets you set and get attributes for subroutines. Setting
attributes takes place at compile time; trying to set invalid attribute
names causes a compile-time error. Calling
attr::get
on a subroutine reference or name returns its list of attribute names.
Notice that attr::get
is not exported. Valid attributes are as follows.
- method
- Indicates that the invoking subroutine is a method.
- locked
-
Setting this attribute is only meaningful when the subroutine or method is
to be called by multiple threads. When set on a method subroutine (i.e. one
marked with the method attribute above), perl ensures that any invocation of it implicitly locks
its first argument before execution. When set on a non-method subroutine,
perl ensures that a lock is taken on the subroutine itself before
execution. The semantics of the lock are exactly those of one explicitly
taken with the
lock
operator immediately after the subroutine is entered.