Passing both a block and its parameters via a const void * and back again

block+parameter_t.m

// A block that saves both your parameter value and the block that processes it, which ...
// ... takes an unsigned long and returns a block that returns an unsigned long 
const unsigned long (^ const __strong predicate_blk_x)(void) = ^ (unsigned long predicate) {
	return ^ const unsigned long (void) {
		return predicate;
	};
}(touch_property); // touch_property is an unsigned int declared and initialized within the scope of this block
    
// A block that return a const void * to the block above, which...
// allows both the block and its parameter (touch_property) to be passed together using a single pointer
const void * (^ const __strong predicate_blk_t_x)(typeof(const unsigned long (^)(void))) = ^ (typeof(const unsigned long (^)(void)) predicate_blk) {
	return Block_copy((const void *)CFBridgingRetain(predicate_blk));
};

// Invoking both blocks above and storing the result in a const void *
const void * predicate_blk_ptr = predicate_blk_t_x(predicate_blk_x);

// A block that takes the const void * above (predicate_blk_ptr) and...
// ... then inokes it to return an unsigned long
const unsigned long l_x = ^ (const void * predicate_expr) {
	return ((typeof(const unsigned long (^)(void)))CFBridgingRelease(predicate_expr))();
}(predicate_blk_ptr);

// Prints the unsigned long that was passed as a parameter (touch_property) above
printf("l_x == %lu\n", l_x);



// !-----------!
// Improved version below
// !-----------!

            /*
             Use the following three blocks to supply the predicate parameter after predicate_blk is passed
             */
            
            const unsigned long (^ const __strong predicate_blk)(const unsigned long) = ^ const unsigned long (const unsigned long predicate) {
                return predicate;
            };
            
            const void * (^ const __strong predicate_blk_t)(typeof(const unsigned long (^)(const unsigned long))) = ^ (typeof(const unsigned long (^)(const unsigned long)) predicate_blk) {
                return Block_copy((const void *)CFBridgingRetain(predicate_blk));
            };
            
            const void * predicate_blk_ptr = predicate_blk_t(predicate_blk);
            const unsigned long l = ^ (const unsigned long predicate) {
            return ^ (const void * predicate_expr) {
                return ((typeof(const unsigned long (^)(const unsigned long)))CFBridgingRelease(predicate_expr))(predicate);
                }(predicate_blk_ptr);
            }(touch_property);
            printf("l == %lu\n", l);


            /*
             Use the following three blocks to supply the predicate parameter before predicate_blk is passed
             */
            
            const unsigned long (^ const __strong predicate_blk_x)(void) = ^ (unsigned long predicate) {
                return ^ const unsigned long (void) {
                    return predicate;
                };
            }(touch_property);
            
            const void * (^ const __strong predicate_blk_t_x)(typeof(const unsigned long (^)(void))) = ^ (typeof(const unsigned long (^)(void)) predicate_blk) {
                return Block_copy((const void *)CFBridgingRetain(predicate_blk));
            };

            const void * predicate_blk_ptr_x = predicate_blk_t_x(predicate_blk_x);
            const unsigned long l_x = ^ (const void * predicate_expr) {
                return ((typeof(const unsigned long (^)(void)))CFBridgingRelease(predicate_expr))();
                }(predicate_blk_ptr_x);
            printf("l_x == %lu\n", l_x);