Javascript return no value [duplicate]

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• How do I return the response from an asynchronous call? 9 answers

I have two functions in javascript to check the code if it exist in database. I just wonder why my codeChecker function does not return anything? It suppose to return a number this is my code Im so confused.

$('#generateCoupon').on('click', app.generateCouponCode);

generateCouponCode: function() {
          var couponInput = $('#couponName');
          var checker = '';
          couponInput.val('');

          var code = "";
          var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

          do {
            for( var i=0; i < 10; i++ )
              code += possible.charAt(Math.floor(Math.random() * possible.length));

            var checker = app.codeChecker('UU9CH0IQ1X'); // Test value loop should not be end because this value is already on Database
            alert(checker); // Test ALERT return nothing
          } while (checker > 0);

          couponInput.val(code);
         },

codeChecker: function(code) {
            var check;

            $.get("/api/check-code",
            { code: code },
            function (data) {
              check = data;
            }
            );
            return check;
          },

My controller:

public function checkCouponCode()

{ $code = Input::get('code');

$model  =  Coupon::where('code', $code)->get();

return Response::make(count($model));

}

Why codeChecker return nothing? The loop should never end because the value I passed to codeChecker is already on database. Im so confused I dont know what's wrong. I just do this to test if the checker is doing good. Thanks.

via Chebli Mohamed