Recursive function in JS

Question

EDIT:

The code i provide includes a asynchron task in each interation, therefor i need the recursive function, my question is how to beautify the code and apply the proper use.

I want to:

• Remove the processTask(); function call and let it call itself instead.

• Choose the best function declaration.

  connection.query(queryString, function (err, rows, fields) {
   if (err) return throwSQLError(err, req, res, connection);
   var rowLength = rows.length;
   var taskIteration = 0;
   // Iterate over all tasks with a recursive function
   var processTask = function () {
   if (taskIteration < rowLength) {
   // I do asynch stuff and call those two lines below
   // in the callback of the asynch operation.
   taskIteration++;
   processTask();
   }
   else {
   // Send JSON to result
   res.json(inputArray);
   // Close MySQL connection
   connection.end();
   }
   };
   processTask();
  });
  

I'm thinking something like this might work:

function processTask(){ // Which function creator to use?
 if (taskIteration < rowLength) {
 // I do asynch stuff and call those two lines below
 // in the callback of the asynch operation.
 taskIteration++;
 processTask();
 }
 else {
 // Send JSON to result
 res.json(inputArray);
 // Close MySQL connection
 connection.end();
 }
}(); // instead of the explicit function call, call the function calls itself

• Dan: Could you supply all of your code? Answers may likely be different given that you're excluding the closure which contains connection, res, taskIteration and rowLength.
• Clemens Himmer: Those closure variables are essentially dispensable, they are part of a node.js mySQL connection and a express.js path and two ints defining for the loop. I basically just want to iterate over my results recursively, but i feel like this solution is not the very best. But if you really think that'd help i'll edit my answer.

Answer 1

Why not just

connection.query(queryString, function (err, rows, fields) {
 if (err) return throwSQLError(err, req, res, connection);
 rows.forEach(function (row) {
 // do what you need to with each row;
 });
 /* or maybe even
 var result = rows.map(function (row) {
 // do what you need to with row and return it
 });
 and then do something with result
 */
 res.json(inputArray); // Not clear from the question where inputArray has come from 
 connection.end();
}

• Clemens Himmer: I think my initial question was articulated really bad, i edited in hope of improvement.