class GroupSequence
A sequence of validation groups. When validating a group sequence, each group will only be validated if all of the previous groups in the sequence succeeded. For example: $validator->validate($address, null, new GroupSequence(array('Basic', 'Strict')));
In the first step, all constraints that belong to the group "Basic" will be validated. If none of the constraints fail, the validator will then validate the constraints in group "Strict". This is useful, for example, i