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POObjective C block declarations conflict
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  1. POObjective C block declarations conflict
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    copied!<p>I've encountered some really annoying issue about objective c blocks. Let's say, we have a code like this:</p> <pre><code>//Class1.h #import &lt;Foundation/Foundation.h&gt; typedef void (^Class1Callback)(BOOL bl); @interface Class1 : NSObject { } - (id)initWithCallback:(Class1Callback)callback; @end //Class2.h #import &lt;Foundation/Foundation.h&gt; typedef enum Class2Enum { Foo, Bar, FooBar } Class2Enum; typedef void (^Class2Callback)(Class2Enum ce); @interface Class2 : NSObject { } - (id)initWithCallback:(Class2Callback)callback; @end //main.c #import "Class1.h" #import "Class2.h" int main(int argc, char *argv[]) { Class1 *class1 = [[Class1 alloc] initWithCallback:^(BOOL bl){ }]; Class2 *class2 = [[Class2 alloc] initWithCallback:^(Class2Enum ce){ }]; } </code></pre> <p>In this code I'm getting an error "incompatible block pointer types initializing 'void (^)(enum Class2Enum)', expected 'Class1Callback'" in line</p> <pre><code>Class2 *class2 = [[Class2 alloc] initWithCallback:^(Class2Enum ce){ }]; </code></pre> <p>But when I just reverse imports in main.c, ie</p> <pre><code>#import "Class2.h" #import "Class1.h" </code></pre> <p>error changes its place and description - now it's in line</p> <pre><code>Class1 *class1 = [[Class1 alloc] initWithCallback:^(BOOL bl){ }]; </code></pre> <p>and description is "incompatible block pointer types initializing 'void (^)(BOOL)', expected 'Class2Callback'"</p> <p>Why does the compiler expect 'Class2Callback' when the method's declaration says that the block type is Class1Callback? I have no idea why it's happening and where I should seek and what I should read to find the answer. Any suggestions?</p>
 

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