C语言实现匿名函数

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#define lambda(return_type, function_body) \

({ \

      return_type $this function_body \

          $this; \

})

#define $ lambda

#define add2int(function_body) $(int, (int _a, int _b){function_body})

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int sum(int *arr, int length, int (*add)(int, int));

int main(int argc, char **argv)

{

    int arr[] = { [0 ... 9] = 1, [10 ... 89] = 2, [90 ... 99] = 3 };

    int ret = sum(arr, sizeof(arr)/sizeof(int), add2int(int c = _a + _b; return c;));

    //add2int返回一个求两个整数和的函数

    printf("sum of arr is %d\n", ret);

}

int sum(int *arr, int length, int (*add)(int, int))

{

    int sum = 0;

    for (int i=0; i < length; i++)

    {

        sum = add(sum, arr[i]);

    }

    return sum;

}

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int ret = sum(arr, sizeof(arr)/sizeof(int), $(int, (int _a, int _b){

    int c = _a + _b;

    return c;

});