不可变的

So, immutability is not strictly the same as having an unchangeable value, it is more subtle.

对象集合是不可变的，所以不可变对象与值不可变是不完全一样的，它更加微妙一个对象的可变性由它

In summary, data that is distributed must be both immutable and stable.

总之，分布式的数据就必须是不可变的，稳定的。

If the data is immutable, it may be practical to allow it to be de-normalized.

假如数据是不可变的，那么允许它不规格化是很实际的。

Strings are immutable, so we need to make a copy.

字符串是不可变的，所以我们需要产生一个拷贝。

The ruling passion of the age," Soddy said,"is to convert wealth into debt— to exchange a thing with present-day real value (a thing that could be stolen, or broken, or rust or rot before you can manage to use it) for something immutable and unchanging , a claim on wealth that has yet to be made.

索迪曾说"这个时代的主要志趣就是将财富转变成债务"——用一个带有现实价值的东西去换取一个永久而不可变的玩艺儿，一个对尚待创造的财富的求取权。

An object's type is also unchangeable.

对象的 类型也是不可变的。

Like numbers, strings are not mutable, so you cannot change an existing string without creating a new one from scratch.

跟数字类型一样，字符串类型也是不可变的，所以你要改变一个字符串就必须通过创建一个新串的方式来实现。

And also denes the possible values for objects of that type.

对象的类型也是不可变的，它用于检测对象支持的操作例如，&&有长度吗？

If a class denes mutable objects and implements a cmp or eq method, it should not implement hash, since the dictionary implementation requires that a key's hash value is immutable (if the object's hash value changes, it will be in the wrong hash bucket).

如果类定义的是可变对象并且实现了 cmp或 eq方法，它就不应该实现 hash，因为字典实现一个散列表的键值是不可变的(如果对象的散列值改变了，它会放在错误的散列表位置中)。

The ruling passion of the age," Soddy said,"is to convert wealth into debt— to exchange a thing with present-day real value (a thing that could be stolen, or broken, or rust or rot before you can manage to use it) for something immutable and unchanging , a claim on wealth that has yet to be made.

索迪曾说&这个时代的主要志趣就是将财富转变成债务&——用一个带有现实价值的东西去换取一个永久而不可变的玩艺儿，一个对尚待创造的财富的求取权。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。