getStringFromFunctionNames(functionList) {
    const ret = [];
    for (let i = 0; i < functionList.length; ++i) {
      const node = this.functionMap[functionList[i]];
      if (node) {
        ret.push(this.functionMap[functionList[i]].toString());
      }
    }
    return ret.join('\n');
  }
@desc Get string from function names
@param {String[]} functionList - List of function to build string
@returns {String} The string, of all the various functions. Trace optimized if functionName given