Documentation

Horde_Constraint: Interface for constraints.
Horde_Constraint_AlwaysFalse: Always returns false
Horde_Constraint_AlwaysTrue: Always returns true
Horde_Constraint_And: Represents a collection of constraints, if one is false, this collection will evaluate to false
Horde_Constraint_Coupler: Interface for grouped (compound, coupled) constraints.
Horde_Constraint_IsEqual: Checks for equality
Horde_Constraint_IsInstanceOf: Checks for an instance of a class
Horde_Constraint_Not: Negates another constraint
Horde_Constraint_Null: Checks if the value is null
Horde_Constraint_Or: Represents a collection of constraints, if any are true, the collection will evaluate to true.
Horde_Constraint_PregMatch: Matches against a PCRE regex