Forward Circulator (Circulator)

Definition

A class Circulator that satisfies the requirements of a forward circulator for the value type T, supports the following operations.

Creation

Circulator c;

Circulator c ( Circulator d);

Operations

bool	c = Circulator d	Assignment.
bool	c == NULL	Test for emptiness.
bool	c != NULL	Test for non-emptiness. The result is the same as !(c == NULL).
bool	c == Circulator d	Test for equality: Two circulators are equal if they refer to the same item.
bool	c != Circulator d	Test for inequality. The result is the same as !(c == d).
T&	* c	Returns the value of the circulator. If Circulator is mutable *c = t is valid. Precondition: c is dereferenceable.
Circulator&	++ c	Prefix increment operation. Precondition: c is dereferenceable. Postcondition: c is dereferenceable.
Circulator	c ++	Postfix increment operation. The result is the same as that of Circulator tmp = c; ++c; return tmp; .

Bidirectional Circulator (Circulator)

Definition

A class Circulator that satisfies the requirements of a bidirectional circulator for the value type T, supports the following operations in addition to the operations supported by a forward circulator.

Operations

Circulator&	-- c	Prefix decrement operation. Precondition: c is dereferenceable. Postcondition: c is dereferenceable.
Circulator	c --	Postfix decrement operation. The result is the same as that of Circulator tmp = c; --c; return tmp; .

Random Access Circulator (Circulator)

Definition

A class Circulator that satisfies the requirements of a random access Circulator for the value type T, supports the following operations in addition to the operations supported by a bidirectional Circulator.

Operations

Circulator&	c += int n	The result is the same as if the prefix increment operation was applied $$n times, but it is computed in constant time.
Circulator	c + int n	Same as above, but returns a new circulator.
Circulator	int n + c	Same as above.
Circulator&	c -= int n	The result is the same as if the prefix decrement operation was applied $$n times, but it is computed in constant time.
Circulator	c - int n	Same as above, but returns a new circulator.
T&	c [ int n]	Returns *(c + n).
int	c - Circulator d	returns the difference between the two circulators within the interval $$[ 1-s , s-1 ] for a sequence size $$s. The difference for a fixed circulator c (or $$d) with all other circulators $$d (or c) is a consistent ordering of the elements in the data structure. There has to be a minimal circulator $$dmin$$ for which the difference c$$- dmin$$ to all other circulators c is non negative.
Circulator	c.min_circulator ()
		Returns the minimal circulator $$cmin$$ in constant time. If $$c has a singular value, a singular value is returned.

There are no comparison operators required.