sub!

/*
 *  call-seq:
 *     sub!(pattern, replacement)    => $_ or nil
 *     sub!(pattern) {|...| block }  => $_ or nil
 *  
 *  Equivalent to <code>$_.sub!(<i>args</i>)</code>.
 */

static VALUE
rb_f_sub_bang(argc, argv)
    int argc;
    VALUE *argv;
{
    return rb_str_sub_bang(argc, argv, uscore_get());
}