Function locateNearestErrorRecoveryRule

src/alasqlparser.js:2149–2166

(state)

            // Return the rule stack depth where the nearest error rule can be found.
            // Return FALSE when no error recovery rule was found.
            function locateNearestErrorRecoveryRule(state) {
                var stack_probe = stack.length - 1;
                var depth = 0;

                // try to recover from error
                for(;;) {
                    // check for error recovery rule in this state
                    if ((TERROR.toString()) in table[state]) {
                        return depth;
                    }
                    if (state === 0 || stack_probe < 2) {
                        return false; // No suitable error recovery rule available.
                    }
                    stack_probe -= 2; // popStack(1): [symbol, action]
                    state = stack[stack_probe];
                    ++depth;
                }
            }

            if (!recovering) {
                // first see if there's any chance at hitting an error recovery rule: