Returns the number of values in a set that match a given value.
- iOS 2.0+
- macOS 10.0+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
The set to examine.
The value for which to search in
the. Comparisons are made using the equal callback provided when
thewas created. If the equal callback was
NULL, pointer equality (in C, ==) is used.
The number of times
value occurs in
the. By definition, sets can not contain duplicate values, so returns
value is contained in
This function uses the equal callback.
value and all elements in the set must be understood by the equal callback.