code: function getSyntacticAutoCompleteSuggestions(input, startRule = 'prog') {
    const lexResult = JDLLexer.tokenize(input);
  
    // ".input" is a setter which will reset the parser's internal state.
    parserSingleton.input = lexResult.tokens;
  
    const syntacticSuggestions = parserSingleton.computeContentAssist(startRule, lexResult.tokens);
  
    // Each suggestion includes additional information such as the "Rule Stack" at suggestion point.
    // This may be handy for advanced implementations, e.g: different logic for suggesting a NAME token in an entity
    // or a field. But it is irrelevant in the scope of the POC.
    return _.uniq(syntacticSuggestions.map(suggestion => suggestion.nextTokenType));
  }
docs: A more complete example can be found here: https://github.com/SAP/chevrotain/blob/master/examples/parser/content_assist/official_feature_content_assist.js#L134