Returns the index of the first object that passes the predicate Block test using the specified enumeration options.
SDKs
- iOS 4.0+
- macOS 10.6+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
Framework
- Foundation
Declaration
func index(options opts: NSEnumeration Options = [], passingTest predicate: (Int, Unsafe Mutable Pointer<Obj CBool>) -> Bool) -> Int
Parameters
opts
A bitmask that specifies the options for the enumeration (whether it should be performed concurrently and whether it should be performed in reverse order). See
NSEnumeration
for the supported values.Options predicate
The Block to apply to elements in the set.
The Block takes two arguments:
- idx
The index of the object.
- stop
A reference to a Boolean value. The block can set the value to
true
to stop further processing of the set. Thestop
argument is an out-only argument. You should only ever set this Boolean to YES within the Block.
The Block returns a Boolean value that indicates whether
obj
passed the test.
Return Value
The index of the first object that passes the predicate test.