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POMixing C pre/post increment/decrement with Objective-C dot operator works?
 

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    <p>Say I have a class with a scalar property type:</p> <pre><code>@property (nonatomic, assign) int myInt; </code></pre> <p>And for clarity, synthesized like:</p> <pre><code>@synthesize myInt = _myInt; </code></pre> <p>If someone had asked me if the following line would work:</p> <pre><code>self.myInt++; </code></pre> <p>I would have said "No". The rationale being that we all know that the dot operator is just syntactic sugar for calling a compiler-generated getter method. So that line is literally:</p> <pre><code>[self myInt]++; </code></pre> <p>If you type that second line into Xcode, it won't compile, stating: "Assigning to 'readonly' return result of an objective-c message not allowed". This makes perfect sense, and it's what I would have expected. Even if that compiled, I would have expected the outcome to increment a copy of the backing ivar on the stack, not the ivar itself.</p> <p>But, the instruction <code>self.myInt++</code> does compile, and it works. It works just as if that dot operator were directly accessing _myInt. By supplying my own getters and setters, I can see that both the getter and the setter are used in the process, in that order, like it was actually:</p> <pre><code>[self setMyInt:[self myInt] + 1]; </code></pre> <p>So, is this an exception to the rule that the dot operator is exactly the same as a method call, or are the <code>{--, ++, +=, -=}</code> operators given special attention by the Objective-C compiler when used with dot notation? I've always thought of them as a C language features with no special considerations for Objective-C. I could see that simple line being very confusing to someone unfamiliar with Objective-C dot notation.</p>
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