Blockoland introduces Objective C blocks, also known as closures, which allow you to group statements together to pass around like objects. Blocks are declared with a return type followed by the block name and arguments inside parentheses. They can be assigned to variables to define the block logic between curly braces. Blocks were originally part of Smalltalk but were not initially prioritized for Objective C. Typedefs can also be used to declare block signatures for readability.

1. Welcome to Blockoland
Objective C Blocks
also known as closures.
Block Name arguments
void (^helloBlock)(void) = ^ void (void){ NSLog(@"Hello, World!"); };
Return Type Block Logic
Blocks were part of Smalltalk They were not a high priority for Objective-C, initially.

2. Block Declarations with
Typedefs
also known as closures.
Block Name arguments
typedef BOOL (^resultHandler)(id result, NSError *error);
Return Type
BOOL (^resultHandler)(id result, NSError *error);
ResultHandler resultHandler;
ResultHandler resultHandler = ^ BOOL (id result, NSError
*error) {
[result performSomeTask];
return YES;
};
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