They work somewhat like pragmas in that they tend to affect the compilation of
your program, and thus will usually work well only when used within a
-C<use>, or C<no>. Most of these are locally scoped, so an inner BLOCK
+C<use>, or C<no>. Most of these are lexically scoped, so an inner BLOCK
may countermand any of these by saying:
no integer;
overload basic Perl operations
+=item re
+
+alter behaviour of regular expressions
+
=item sigtrap
enable simple signal handling