hasmodel.has(attribute) Returns true if the attribute is set to a non-null or non-undefined value.

defaultsmodel.defaults or model.defaults() The defaults hash (or function) can be used to specify the default attributes for

pairs

changedAttributesmodel.changedAttributes([attributes]) Retrieve a hash of only the model's attributes that have changed since the

hasChangedmodel.hasChanged([attribute]) Has the model changed since its last

changedmodel.changed The changed property is the internal hash containing all the attributes that have changed since its last

urlmodel.url() Returns the relative URL where the model's resource would be located on the server. If your models are located somewhere

escapemodel.escape(attribute) Similar to get, but returns

values

validationErrormodel.validationError The value returned by validate