Validator that fails with message if the value is unspecified.
Message that is stored in Element.errors.
Validator that fails with message if the value is not unserializable.
Message that is stored in Element.errors.
Validator that fails with message if the value is false-ish.
Message that is stored in Element.errors.
Validator that fails with message if the value is true-ish.
Message that is stored in Element.errors.
Validator that fails with message if the length of the value is equal to or longer than the given upperbound.
Message that is stored in Element.errors. {upperbound} in the message is substituted with the given upperbound.
Validator that fails with message if the length of the value is equal to or shorter than the given lowerbound.
Message that is stored in Element.errors. {lowerbound} in the message is substituted with the given lowerbound.
Validator that fails with message if the length of the value is less than or equal to start or greater than or equal to end.
Message that is stored in Element.errors. {start} and {end} is substituted with the given start and end.
A validator that fails with "Not a valid value." if the value is not contained in options.
Message that is stored in Element.errors.
Validator that fails with message if the value is greater than or equal to upperbound.
Message that is stored in Element.errors. {upperbound} is substituted with the given upperbound.
Validator that fails with message if the value is less than or equal to lowerbound.
Message that is stored in the Element.errors. {lowerbound} is substituted with the given lowerbound.
Validator that fails with message if the value is less than or equal to start or greater than or equal to end.
Message that is stored in Element.errors. {start} and {end} are substituted with the given start and end.
Validator that fails with message if two items in the value are unequal.
The items are defined with the tuples a and b each of which consist of two elements (label, key). The key is used to determine the item to compare and the label is used for substitution in the message.
Message that is stored in Element.errors. {a} and {b} are substituted with the labels in the given a and b.
Validator that fails with message if two attributes of the value are unequal.
Similar to ItemsEqual the attributes are defined with the tuples a and b each of which consists of two element in the form (label, attribute_name). attribute_name is used to determine the attributes to compare and the label is used for substitution in the message.
Message that is stored in Element.errors. {a} and {b} are substituted with the labels in the given a and b.
A validator that fails with message, if the value of the validated e-mail is not a valid e-mail address.
While this validator works on valid e-mail addresses it is not expected to pick up all bad e-mail addresses. The reason for this is that parsing e-mail addresses is very complicated, costly, probably would wrongly recognize some valid e-mail addresses as invalid and cannot determine if someone is reachable with this address.
If you want to truly validate e-mail addresses you need to send an e-mail and wait for a response.
Message that is stored in the Element.errors.