An evil idea for writing a metalanguage on top of Objective C where the syntax is actually pleasant. Nobody should ever, ever do this.

Evil.h

    //Interface

    @interface NSObject (Evil)
    
    @property (readonly) BOOL (^equals)(id object);
    
    @end

    
    @interface NSArray (Evil)
    
    @property (readonly) NSArray *(^append)(id object);
    
    @end

Evil.m

    //Implementation

    @implementation NSObject (Evil)
    
    - (BOOL (^)(id object))equals
    {
        id __weak weakSelf = self;
        return ^(id object) {
            return [weakSelf isEqualTo:object];
        };
    }
    
    @end

    
    @implementation NSArray(Evil)
    
    - (NSArray *(^)(id object))append
    {
        NSArray *__weak weakSelf = self;
        return ^(id object) {
            return [weakSelf arrayByAddingObject:object];
        };
    }
    
    @end

EvilTests.m

    //Tests
    
    - (void)testAppend
    {
        NSArray *input = @[@"foo"];
        NSArray *output = @[@"foo", @"bar"];
        NSAssert(input.append(@"bar").equals(output), @"Append didn't work");
    }