remove empty json array from array object while doing map in mule 3

How can i apply the filter to remove empty array while doing transformation. I tried to apply sizeOf ($) != 0 but that is not working. I am able to do this by creating function but here i have to remove while doing map.kindly suggest solution for that.

            %dw 1.0
            %output application/json
            ---
            {
            employees: {
                employee:  (flowVars.varInputData.request.application.applicants) map ((applicant , indexOfApplicant) -> {
                        (flowVars.varMbResponse.application.applicants filter ($.customerID == applicant.customerID) map {
                        "source": "EMI_IMP",
                        "loanData": ($.customBureauResponse.customResponse.accountList map {
                                    "customerGender": applicant.gender
                })
                })

                })  
            }
            }

Response from the dwl:

            {
            "EMIComputations": {
                "eMIComputation": [{
                        "source": "EMI_IMP",
                        "loanData": [{
                                "customerGender": "F",
                            },
                            {
                                "customerGender": "M",
                            }
                        ]
                    },
                    {

                    },
                    {

                    }
                ]
            }
            }

expected output:

            "EMIComputations": {
                "eMIComputation": [{
                        "source": "EMI_IMP",
                        "loanData": [{
                                "customerGender": "M",
                            },
                            {
                                "customerGender": "M",
                            }
                        ]
                    }
                ]
            }
            }