/*
 *  call-seq:
 *    ripper#column   -> Integer
 *
 *  Return column number of current parsing line.
 *  This number starts from 0.
 */
static VALUE
ripper_column(VALUE self)
{
    struct parser_params *parser;
    long col;

    TypedData_Get_Struct(self, struct parser_params, &parser_data_type, parser);
    if (!ripper_initialized_p(parser)) {
        rb_raise(rb_eArgError, "method called for uninitialized object");
    }
    if (NIL_P(parser->parsing_thread)) return Qnil;
    col = parser->tokp - parser->parser_lex_pbeg;
    return LONG2NUM(col);
}