/*
 *  call-seq:
 *     str.hex   => integer
 *  
 *  Treats leading characters from <i>str</i> as a string of hexadecimal digits
 *  (with an optional sign and an optional <code>0x</code>) and returns the
 *  corresponding number. Zero is returned on error.
 *     
 *     "0x0a".hex     #=> 10
 *     "-1234".hex    #=> -4660
 *     "0".hex        #=> 0
 *     "wombat".hex   #=> 0
 */

static VALUE
rb_str_hex(str)
    VALUE str;
{
    return rb_str_to_inum(str, 16, Qfalse);
}