objcjure

A clojure DSL for calling objective c code.

Syntax

Literals

Clojure Type	Objective-C Type
`nil`	NULL (null pointer)
`boolean`	BOOL
`byte`	int8
`short`	int16
`int`	int32
`long`	int64
`float`	float32
`double`	float64

Examples:

Clojure	Objective-C
`nil`	`NULL`
`true`	`YES`
`false`	`NO`
`(byte 1)`	`1`
`(short 1)`	`1`
`(int 1)`	`1`
`1`	`1`
`(float 1.0)`	`1.0`
`1.0`	`1.0`

Coercions

Coercions for common objective-c types are also provided via @.

Clojure	Objective-C
`@"mystring"`	`@"mystring"`
`@true`	`@YES`
`@false`	`@NO`
`@1`	`@1`
`@1.0`	`@1.0`
`@{@"key" @"value"}`	`@{@"key" @"value"}`
`@[@1, @2]`	`@[@1 @2 ]`
`@#{@1, @2}`	`[NSSet setWithArray: @[@1 @2 ]]`

Symbols

If a symbol can be resolved in the current context, it will use the value of the binding. Otherwise, it is assumed to be the name of a class which will be looked up at runtime.

Function Calls

Function calls are represented by vectors (similar to how they appear in objective-c).

Some examples:

clojure	objective-c
`[NSArray :array]`	`[NSArray array]`
`[nsdict :setValue:forKey info @"nowPlayingInfo"]`	`[nsdict setValue:info forKey:@"nowPlayingInfo"]`

Note the differences:

the method selector is a keyword
the method selector is the full selector (splitting up the selector into its parts to more closely match objective c may be supported in the future).
No trailing : in method name!

The return type is assumed to be a pointer, but can be coerced via type hint.


;; Return a long.
(objc ^long [[NSArray :array] :count])
;; Return void
(objc ^void [my-player :play])

;; Return a type by hinting the dtype next struct name
(objc ^cm_time [~(:player @pod-state) :currentTime])

The following type hints are supported:

byte
short
int
long
float
double
pointer
pointer?
void
The name (as a symbol) of a dtype next struct.

Blocks

Anonymous functions are automatically coerced to blocks. The return value and args are assumed to be of type pointer, but can be specified via type hint.

(objc ^void
      [[AVAudioSession :sharedInstance]
       :activateWithOptions:completionHandler
       0
       (fn ^void [^byte activated error]
         (println "activated" activated error))])