How to use the aurelia-validation.validationMessages function in aurelia-validation

StringRules.prototype.setCustomMessages = function () {
        aurelia_validation_1.validationMessages.minLength = this.configuration.messages.minLength || aurelia_validation_1.validationMessages.minLength;
        aurelia_validation_1.validationMessages.maxLength = this.configuration.messages.maxLength || aurelia_validation_1.validationMessages.maxLength;
        aurelia_validation_1.validationMessages.matches = this.configuration.messages.pattern || aurelia_validation_1.validationMessages.matches;
        aurelia_validation_1.validationMessages.email = this.configuration.messages.format_email || aurelia_validation_1.validationMessages.email;
    };
    StringRules.prototype.add = function () {

StringRules.prototype.setCustomMessages = function () {
        aurelia_validation_1.validationMessages.minLength = this.configuration.messages.minLength || aurelia_validation_1.validationMessages.minLength;
        aurelia_validation_1.validationMessages.maxLength = this.configuration.messages.maxLength || aurelia_validation_1.validationMessages.maxLength;
        aurelia_validation_1.validationMessages.matches = this.configuration.messages.pattern || aurelia_validation_1.validationMessages.matches;
        aurelia_validation_1.validationMessages.email = this.configuration.messages.format_email || aurelia_validation_1.validationMessages.email;
    };
    StringRules.prototype.add = function () {

StringRules.prototype.setCustomMessages = function () {
        aurelia_validation_1.validationMessages.minLength = this.configuration.messages.minLength || aurelia_validation_1.validationMessages.minLength;
        aurelia_validation_1.validationMessages.maxLength = this.configuration.messages.maxLength || aurelia_validation_1.validationMessages.maxLength;
        aurelia_validation_1.validationMessages.matches = this.configuration.messages.pattern || aurelia_validation_1.validationMessages.matches;
        aurelia_validation_1.validationMessages.email = this.configuration.messages.format_email || aurelia_validation_1.validationMessages.email;
    };
    StringRules.prototype.add = function () {

CommonRules.prototype.setCustomMessages = function () {
        aurelia_validation_1.validationMessages.const = this.configuration.messages.const || aurelia_validation_1.validationMessages.equals;
    };
    CommonRules.prototype.add = function () {

StringRules.prototype.setCustomMessages = function () {
        aurelia_validation_1.validationMessages.minLength = this.configuration.messages.minLength || aurelia_validation_1.validationMessages.minLength;
        aurelia_validation_1.validationMessages.maxLength = this.configuration.messages.maxLength || aurelia_validation_1.validationMessages.maxLength;
        aurelia_validation_1.validationMessages.matches = this.configuration.messages.pattern || aurelia_validation_1.validationMessages.matches;
        aurelia_validation_1.validationMessages.email = this.configuration.messages.format_email || aurelia_validation_1.validationMessages.email;
    };
    StringRules.prototype.add = function () {