How to use the @rxweb/reactive-form-validators.RxwebValidators.maxDate function in @rxweb/reactive-form-validators

() => {
          expect(RxwebValidators.maxDate()(new FormControl(undefined))).toBeNull();
        });

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            registrationDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30)  ,message:'{{0}} exceeds the Maximum Date Limit' })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            registrationDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30) })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            userName:['',], 
            admissionDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30)  ,conditionalExpression:'x => x.userName == "Bharat"' })], 
            birthDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30)  ,conditionalExpression:(x,y) => x.userName == "Bharat"  })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            userName:['',], 
            admissionDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30)  ,conditionalExpression:'x => x.userName == "Bharat"' })], 
            birthDate:['', RxwebValidators.maxDate({value:new Date(2018,7,30)  ,conditionalExpression:(x,y) => x.userName == "Bharat"  })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            registrationDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,message:'{{0}} exceeds the Maximum Date Limit' })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            userName:['',], 
            allocationDate:['', RxwebValidators.maxDate({value:'07/30/2018' })], 
            birthDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,conditionalExpression:(x,y) => x.userName == "Bharat"  })], 
            admissionDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,conditionalExpression:'x => x.userName == "Bharat"' })], 
            registrationDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,message:'{{0}} exceeds the Maximum Date Limit' })], 
            enrollmentDate:['',], 
            lastRegistrationDate:['', RxwebValidators.maxDate({fieldName:'enrollmentDate' })], 
            confirmationDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,operator:'<' })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            confirmationDate:['', RxwebValidators.maxDate({value:'07/30/2018'  ,operator:'<' })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            enrollmentDate:['',], 
            lastRegistrationDate:['', RxwebValidators.maxDate({fieldName:'enrollmentDate' })], 
        });
    }
}

ngOnInit() {
        this.userFormGroup = this.formBuilder.group({
            registrationDate:['', RxwebValidators.maxDate({value:'07/30/2018' })], 
        });
    }
}