Here lists all the accessors currently available in Hydrant. Accessors abstract the details of getting and setting values from objects so that each Mapper does not have to implement them individually. All the functions listed here return objects that conform to the Accessor protocol.
You might be thinking the overload functions listed require Objective-C++, but clang supports function overloading.
This accessor provides KeyPath-styled access to objects. They only support the dot-access from KeyPath to walk nested data structures. Like HYDAccessKey, this mapper will correctly convert boxed typed into their native c-types since it internally uses -[valueForKey:] and -[setValue:forKey:].
If given [NSNull null] values, when setting values, then that assignment is considered a no-op, not assigning to nil. This is because the accessor cannot safely assign nil vs [NSNull null] (eg - property vs dictionary key).
There is a macro to create this accessor:
HYDAccessKeyPath(...)
Which takes a variatic sequence of NSStrings that represent the keyPaths to walk. Giving multiple keyPaths will generate a large array value and the expected input values when setting it too.
The macro is based off of the c function:
HYDAccessKeyPathInArray(NSArray *keyPaths)
As the name suggests, accepts an explicit array of keyPaths.
This accessor provides KVC-styled access to objects. Like HYDAccessKeyPath, this mapper will correctly convert boxed typed into their native c-types since it internally uses -[valueForKey:] and -[setValue:forKey:].
If given [NSNull null] values, when setting values, then that assignment is considered a no-op, not assigning to nil. This is because the accessor cannot safely assign nil vs [NSNull null] (eg - property vs dictionary key).
There is a macro to create this accessor:
HYDAccessKey(...)
Which takes a variatic sequence of NSStrings that represent the keys to walk. Giving multiple keyPaths will generate a large array value and the expected input values when setting it too.
The macro is based off of the c function:
HYDAccessKeyInArray(NSArray *keyPaths)
As the name suggests, accepts an explicit array of keys.
Warning
This is feature alpha. It’s API and capabilities may change between versions. Please avoid use if you can’t accept instability.
This accessor provides index access to objects. This is useful for extracting values from an array where the order has a specific, known meaning.
If given [NSNull null] values, when setting values, then that assignment is valid. This is unlike the other mappers. Also, this accessor will place add [NSNull null] instances to arrays if they do not meet the size requirement that the accessor expects to update indicies.
There is a macro to create this accessor:
HYDAccessIndex(...)
Which takes a variatic sequence of NSNumbers that represent the indicies to read. Giving multiple indicies will generate a large array value and the expected input values when setting it too.
The macro is based off of the c function:
HYDAccessIndiciesInArray(NSArray *indicies)
As the name suggests, accepts an explicit array of indicies (NSNumbers).
This is a helper function that maps to the default accessor that Hydrant’s mappers prefer. Handy if you need a default but don’t have an opinion for your own mappers. Hydrant currently maps this to HYDAccessKeyPath.
There are two variants:
HYDAccessDefault(NSString *field)
HYDAccessDefault(NSArray *fields)
Which currently ties to the same behavior as HYDAccessKeyPath.