Question

I have a function like so:

- (void)addBalloon:(COLOR)color:(VELOCITY)velocity:(LOCATION)location 

Where COLOR is an enum, and VELOCITY and LOCATION are structs defined in a constants header file..

VELOCITY and LOCATION both store two ints, x and y.

When calling this method, I would call it like so:

VELOCITY vel;
LOCATION loc;

vel.x = 100.0;
vel.y = 0.0;

loc.x = 10.0;
loc.y = 10.0;

[self addBalloon:Red:vel:loc];

But to me, this seems disorganized. I would like to call the function directly in one line while creating the struct on the line..

Here is my question: I’m not sure if this can be done using #define.. but if it can’t.. is the only other viable option creating a function that returns VELOCITY or LOCATION and takes inputs x, and y?

I would like to do something like the following:

[self addBalloon:Red:VELOCITY(100.0, 0.0):LOCATION(10.0, 10.0)];

Answer 1

You can use the C99 syntax for designated initialisers:

[self addBalloon:Red:(VELOCITY){100.0, 0.0}:(LOCATION){10.0, 10.0}];

or

[self addBalloon:Red:(VELOCITY){.x=100.0, .y=0.0}:(LOCATION){.x=10.0, .y=10.0}];