namespace System.Diagnostics.Contracts { public static class Contract { public static event EventHandler<ContractFailedEventArgs> ContractFailed; public static void Assert(bool condition); public static void Assert(bool condition, string userMessage); public static void Assume(bool condition); public static void Assume(bool condition, string userMessage); public static void EndContractBlock(); public static void Ensures(bool condition); public static void Ensures(bool condition, string userMessage); public static void EnsuresOnThrow<TException>(bool condition) where TException : Exception; public static void EnsuresOnThrow<TException>(bool condition, string userMessage) where TException : Exception; public static bool Exists(int fromInclusive, int toExclusive, Predicate<int> predicate); public static bool Exists<T>(IEnumerable<T> collection, Predicate<T> predicate); public static bool ForAll(int fromInclusive, int toExclusive, Predicate<int> predicate); public static bool ForAll<T>(IEnumerable<T> collection, Predicate<T> predicate); public static void Invariant(bool condition); public static void Invariant(bool condition, string userMessage); public static T OldValue<T>(T value); public static void Requires(bool condition); public static void Requires(bool condition, string userMessage); public static void Requires<TException>(bool condition) where TException : Exception; public static void Requires<TException>(bool condition, string userMessage) where TException : Exception; public static T Result<T>(); public static T ValueAtReturn<T>(out T value); } }