+ parser_trace(trace, &p,
+ tk, states, non_term, config->known_count);
+
+ if (tk->num == TK_in) {
+ tos->indents += 1;
+ tos->since_newline = 0;
+ tos->since_indent = 0;
+ if (!states[tos->state].starts_line)
+ tos->newline_permitted = 0;
+ free(tk);
+ tk = NULL;
+ parser_trace_action(trace, "Record");
+ continue;
+ }
+ if (tk->num == TK_out) {
+ if (states[tos->state].reduce_size >= 0 &&
+ states[tos->state].reduce_size <= tos->since_indent)
+ goto force_reduce;
+ if (states[tos->state].min_prefix >= tos->since_indent) {
+ // OK to cancel
+ struct frame *in = tos - tos->since_indent;
+ in->indents -= 1;
+ if (in->indents == 0) {
+ /* Reassess since_indent and newline_permitted */
+ if (in > p.stack) {
+ in->since_indent = in[-1].since_indent + 1;
+ in->newline_permitted = in[-1].newline_permitted;
+ } else {
+ in->since_indent = 0;
+ in->newline_permitted = 0;
+ }
+ if (states[in->state].starts_line)
+ in->newline_permitted = 1;
+ while (in < tos) {
+ in += 1;
+ in->since_indent = in[-1].since_indent + 1;
+ if (states[in->state].starts_line)
+ in->newline_permitted = 1;
+ else
+ in->newline_permitted = in[-1].newline_permitted;
+ }
+ }
+ free(tk);
+ tk = NULL;
+ parser_trace_action(trace, "Cancel");
+ continue;
+ }
+ // fall through to error handling as both SHIFT and REDUCE
+ // will fail.
+ }
+ if (tk->num == TK_newline) {
+ if (!tos->newline_permitted) {
+ free(tk);
+ tk = NULL;
+ parser_trace_action(trace, "Discard");
+ continue;
+ }
+ if (tos->since_newline > 1 &&
+ states[tos->state].reduce_size >= 0 &&
+ states[tos->state].reduce_size <= tos->since_newline)
+ goto force_reduce;
+ }
+ if (shift(&p, tk->num, 0, tk->num == TK_newline, tk, states)) {
+ tk = NULL;
+ parser_trace_action(trace, "Shift");