what “this._find(callback)” means in Mongoose find() method?

Question

As I looked through the source code of the find() of mongoose.js , which looks like following:

    Query.prototype.find = function(conditions, callback) {
  if (typeof conditions === 'function') {
    callback = conditions;
    conditions = {};
  }

  conditions = utils.toObject(conditions);

  if (mquery.canMerge(conditions)) {
    this.merge(conditions);
  }

  prepareDiscriminatorCriteria(this);

  try {
    this.cast(this.model);
    this._castError = null;
  } catch (err) {
    this._castError = err;
  }

  // if we don't have a callback, then just return the query object
  if (!callback) {
    return Query.base.find.call(this);
  }

  this._find(callback);

  return this;
};

I really don't understand the part

this._find(callback);

what this means? what is the _find in javascript?

Thanks in advance!

Max

Answer 1

what “this._find(callback)” means in Mongoose find() method?

It's a function call. It seems this._find is a supposed to be a function. That function is called and passed the value of callback .

what is the _find in javascript?

Nothing special. It's simply a property with name _find . If you continue looking through the source code, you might discover its definition somewhere.