Dot Operator in Objective-C 2.0

Question

Just picking up Objective-C 2.0 and wanted to know if there is any advantage in using the dot operator for accessing properties instead of the "old" way. Short example of what I mean.

"old" way:

 [myFraction setNumerator: 1];
 [myFraction setDenominator: 3];

"new" way:

 myFraction.numerator = 1;
 myFraction.denominator = 3;

Thanks!

Rodrigo

Answer 1

The only difference is ease of typing and readability. The opinion of which is more readable differs from person to person :)

Answer 2

I'll argue for the old way:

The square-bracket syntax maxes it obvious that you are accessing the members of an Objective-C object, while the dot syntax indicates that you are dealing with a C struct (or union).

Beyond than that, it is simply a matter of personal choice and more/less typing.

Answer 3

I use the dot syntax when I'm descending an object and use the bracket to actually set a property.

Like so:

[self.view setFrame:CGRectMake(0, 0, 320, 480)];

Instead of:

[[self view] setFrame:CGRectMake(0, 0, 320, 480)];

Answer 4

I actually like the new syntax - but maybe because I work as Python programmer.

The dot-property syntax meshes nicely with key-paths in KVC/KVO. It looks neater to my eyes than nested brackets (and I like scheme, so I'm not opposed to parentheses nesting!), and makes it explicit when you are accessing a property, rather than passing a message - even though the mechanism is the same.

And, I see property access of an object being (basically) the same operation as accessing members of a struct or union, so the syntax should be the same.

Answer 5

C++ and C# programmers probably will more naturally adapt to the dot operator when accessing member variables since it has similar usage in those languages.