objectivec

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^{ … }

NSArray *urls = [NSArray arrayWithObjects:@"http://www.apple.com/", 
    @"http://www.google.com/", @"http://www.example.com/", nil];

NSOperationQueue *q = [[NSOperationQueue alloc] init];
[q setSuspended:YES];

void (^loadingBlock)(NSURL *url) = ^(NSURL *url) {  
    NSLog(@"started downloading %@", url);
    NSString *contents = [NSString stringWithContentsOfURL:url];
    NSLog(@"downloaded %@ (%d chars)", url, [contents length]);
};

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