What is the logic of "no label" for 1st argument of a function

[Vishwas Gagrani]

Curious to know, if there is any logic behind the syntactical structure, where 1st argument is not labelled, but following arguments only need labelling ?

[myObject myFunction:firstArgument theSecondArgument:secondArgument];

Or is it just how it is made. There is no logic. ?

[KoolStar]

Typically if you were to create a method signature it would be something that would label the first argument itself. This can be seen with almost any of apples method signatures.

UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCELL_IDENTIFIER];

We can see that the first argument is prefixed with with initWithStyle thus labeling the first argument as a style and telling us that the function call is an init function.

Another such example in MKMapKit, imagine _mapView is an MKMapView reference.

[_mapView convertCoordinate:coordinate toPointToView:self.view];

We are converting a coordinate to a specific view that is provided by the first argument.

The logic behind the naming is to be descriptive that is the nature of Objective-C.

[Vishwas Gagrani]

ok, thnx for explanation.

However, when i think something like this :

[ mathObj addTheNumbers:number0  number1:number1 ]

it looks to me awkward. But may be it's just a matter of practice.

[phr0ze]

Originally Posted by Vishwas Gagrani

ok, thnx for explanation.

However, when i think something like this :

[ mathObj addTheNumbers:number0  number1:number1 ]

it looks to me awkward. But may be it's just a matter of practice.

Wouldn't it be better to pass that in another way?

[KoolStar]

Originally Posted by phr0ze

Wouldn't it be better to pass that in another way?

If I were writing that method I would most likely name it some to this affect.

[mathObj add:sumNumber to:sumNumber];

[ArtOfWarfare]

Shouldn't that be a class method instead of an instance method?

[KoolStar]

Originally Posted by ArtOfWarfare

Shouldn't that be a class method instead of an instance method?

Honestly something as trivial as adding numbers should be a function not even a method of a class or object. Whether it be a static or instance class.

In that case it would be:

int add(int x, int y)
{
     return x + y;
}

With usage of:

int result;
result = add(10, 20);

I think the original poster was simply asking about naming convention used for objective-c methods regardless or static or instance.

[PhoneyDeveloper]

addNumber:toNumber:

https://developer.apple.com/library/...uidelines.html