Function deepClone

Remarks

This function uses an internal Map to handle circular references safely, preventing infinite recursion during deep cloning. The cloning depth is limited to 1000; deeper structures throw a RangeError. Holes in sparse arrays are preserved.

此函数使用内部的 Map 来安全处理循环引用，防止深度克隆过程中的无限递归。 克隆深度上限为 1000，超出后抛出 RangeError；稀疏数组中的空洞会被保留。