Original
Dynamic array types
A dynamic-array variable occupies
four bytes of memory which contain a pointer to the dynamically allocated
array. When the variable is empty (uninitialized) or holds a zero-length array,
the pointer is nil and no dynamic memory is associated with the variable.
For a nonempty array, the variable points to a dynamically allocated block of
memory that contains the array in addition to a 32-bit length indicator and a
32-bit reference count. The table below shows the layout of a dynamic-array
memory block.
Offset |
Contents |
|
-8 |
32-bit reference-count |
|
-4 |
32-bit length indicator (number of elements) |
|
0..Length * (size of element) -1 |
array elements |
See also
译文
动态数组类型
一个动态数组变量占用4个字节来保存指向动态分配数组的指针。当变量为空（未初始化的）或者保存了一个零长度的数组时，指针为nil并且没有任何动态内存与之相关联。对于一个非空的动态数组，变量指向一个动态分配的内存块，该内存块包含了数组、一个32位的长度指示器、一个32位的引用计数器。下表时动态数组内存块的布局：
偏移量 |
内容 |
|
-8 |
32位的引用计数器 |
|
-4 |
32位的长度指示器（元素个数） |
|
0..Length * (size of element) -1 |
数组元素 |