How to use the ngx-custom-validators.CustomValidators.equal function in ngx-custom-validators

_.forEach(validators, (validator: PageControlValidator) => {
            if (validator.isActive) {
                switch (validator.validatorType) {
                    case ValidatorType.Required:
                        formValidators.push(Validators.required)
                        break
                    case ValidatorType.Equal:
                        formValidators.push(CustomValidators.equal(JSON.parse(validator.validatorOption)))
                        break
                    case ValidatorType.EqualTo:
                        const foundEqualToControl = availableControls[validator.validatorOption]
                        if (!!foundEqualToControl) {
                            formValidators.push(CustomValidators.equalTo(foundEqualToControl))
                        }
                        break
                    case ValidatorType.Email:
                        formValidators.push(CustomValidators.email)
                        break
                    case ValidatorType.Number:
                        formValidators.push(CustomValidators.number)
                        break
                    case ValidatorType.NumberRange:
                        formValidators.push(CustomValidators.range(JSON.parse(validator.validatorOption)))
                        break