在快速给出错误中使用块“在其自己的初始值内使用变量”

This is my code in obj-c

这是我在obj-c中的代码

__block NSString *requestReference = [self operation:method url:url parameters:parameters headers:headers success:^(NSURLSessionDataTask *task, id responseObject) {
NSError *error = [NSError errorWithSessionTask:task responseObject:responseObject];
if (error) {
    NSLog(@"error - %@", error);
    [delegate requestWithReference:requestReference didFinishWithBusinessError:error];
} else {
    id responseModel;
    if (modelClass && responseObject) {
        if ([responseObject isKindOfClass:[NSDictionary class]]) {
            // if response is a dictionary, create model out of it
            responseModel = [modelClass objectFromDictionary:responseObject error:&error];
        } else if ([responseObject isKindOfClass:[NSArray class]]) {
        }
    }
} } failure:^(NSURLSessionDataTask *task, NSError *error) {
[delegate requestWithReference:requestReference didFailWithError:error]; }];
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