how to return a variable outside of javascript function that is inside a function?

Question

So I have

  function find_coord(lat, lng) {
              var smart_loc;
      var latlng = new google.maps.LatLng(lat, lng);
        geocoder = new google.maps.Geocoder();
        geocoder.geocode( { 'latLng': latlng }, function(results, status) {
            if (status == google.maps.GeocoderStatus.OK) {
                smart_loc = new smart_loc_obj(results);
            } else {
                smart_loc = null;
            }
        });

        return smart_loc;
}

I want to return the smart_loc variable/object but it is always null because the scope of the function(results, status) doesn't reach the smart_loc declared in the find_coord function. So how do you get a variable inside the function(results, status) out?

Answer 1

You can do:

var smart_loc;

function find_coord(lat, lng) {
  var latlng = new google.maps.LatLng(lat, lng);
    geocoder = new google.maps.Geocoder();
    geocoder.geocode( { 'latLng': latlng }, function(results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
            smart_loc = new smart_loc_obj(results);
        } else {
            smart_loc = null;
        }
    });
}

Or if you need to run a function when smart_loc changes:

function find_coord(lat, lng, cb) {
          var smart_loc;
  var latlng = new google.maps.LatLng(lat, lng);
    geocoder = new google.maps.Geocoder();
    geocoder.geocode( { 'latLng': latlng }, function(results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
            smart_loc = new smart_loc_obj(results);
        } else {
            smart_loc = null;
        }

        cb(smart_loc);
    });
}

then call:

find_coord(lat, lng, function (smart_loc) {
    //
    // YOUR CODE WITH 'smart_loc' HERE
    //
});