Instance Method

countByEnumerating(with:objects:count:)

Returns by reference a C array of objects over which the sender should iterate, and as the return value the number of objects in the array.

Required.

Declaration

func countByEnumerating(with state: UnsafeMutablePointer<NSFastEnumerationState>, objects buffer: AutoreleasingUnsafeMutablePointer<AnyObject?>, count len: Int) -> Int

Parameters

state

Context information that is used in the enumeration to, in addition to other possibilities, ensure that the collection has not been mutated.

stackbuf

A C array of objects over which the sender is to iterate.

len

The maximum number of objects to return in stackbuf.

Return Value

The number of objects returned in stackbuf. Returns 0 when the iteration is finished.

Discussion

The state structure is assumed to be of stack local memory, so you can recast the passed in state structure to one more suitable for your iteration.