我们可以使用嵌套的for循环来遍历嵌套的字典。对于每个嵌套的字典，我们使用递归遍历。我们还需要检查每个字典中的值是否是另一个嵌套的字典或其他类型的数据。以下是一个示例代码，可以用来遍历嵌套的字典：

func iterateDictionary(dict: [String: Any]) {
    for (key, value) in dict {
        if let innerDict = value as? [String: Any] {
            iterateDictionary(dict: innerDict)
        } else {
            print("\(key): \(value)")
        }
    }
}

// 示例字典
let dict: [String: Any] = [
    "name": "Tom",
    "age": 30,
    "details": [
        "address": "123 Main St",
        "phone": "555-555-5555",
        "emergency_contacts": [
            "name": "Bob",
            "phone": "555-123-4567"
        ]
    ]
]

iterateDictionary(dict: dict)

输出：

name: Tom
age: 30
address: 123 Main St
phone: 555-555-5555
name: Bob
phone: 555-123-4567