C++ named requirements:
RandomNumberEngineAdaptor (od C++11)

A RandomNumberEngineAdaptor is a RandomNumberEngine that transforms the output of another RandomNumberEngine, the latter of which is termed a base engine.

Requirements

Given

• B, a RandomNumberEngine
• b, an object of type B
• A, a RandomNumberEngineAdaptor, adapting B as a base engine
• a, an object of type A

function	semantics
A::A();	The base engine is initialized as if by its default constructor.
bool operator==(const A& lhs, const A& rhs);	Returns whether lhs's base engine is equal to rhs's base engine or not.
A::A(result_type s);	The base engine is initialized with s.
template<class Sseq> A::A(Sseq& q);	The base engine is initialized with q.
void seed();	Invokes b.seed().
void seed(result_type s);	Invokes b.seed(s).
template<class Sseq> void seed(Sseq& q);	Invokes b.seed(q).

Furthermore

• The complexity of each function of A does not exceed the complexity of the function of B
• The state of A includes the state of B
• The size of A's state is no less than the size of b
• Copying A's state includes copying B's state
• The textual representation of A includes the textual representation of B

Standard library

The following standard library facilities satisfy RandomNumberEngineAdaptor:

pub	discard_block_engine(C++11)	discards some output of a random number engine
pub	independent_bits_engine(C++11)	packs the output of a random number engine into blocks of a specified number of bits
pub	shuffle_order_engine(C++11)	delivers the output of a random number engine in a different order