, , $error ngModelController?
return {
template: '<input ng-model="value" type="number" /><span ng-bind="error | json"></span>',
scope : {},
link: function(scope, elem, attr) {
scope.error = elem.find('input').controller('ngModel').$error;
}
}
http://plnkr.co/edit/wzuWT1lVevCLHkLLBIAT?p=preview