+=head1 CONSTANTS
+
+=head2 C<A_THREADSAFE>
+
+True iff the module could have been built with thread-safety features enabled.
+This constant only has a meaning with your perl is threaded ; otherwise, it'll always be false.
+
+=head2 C<A_FORKSAFE>
+
+True iff this module could have been built with fork-safety features enabled.
+This will always be true except on Windows where it's false for perl 5.10.0 and below .
+
+=head1 CAVEATS
+
+The pragma doesn't apply when one dereferences the returned value of an array or hash slice, as in C<< @array[$id]->{member} >> or C<< @hash{$key}->{member} >>.
+This syntax is valid Perl, yet it's discouraged as the slice is here useless since the dereferencing enforces scalar context.
+If warnings are turned on, Perl will complain about one-element slices.
+