
Extracting Immutable Objects - luu
https://push.cx/2013/extracting-immutable-objects
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benjiweber
Most seem like Value
Objects[http://martinfowler.com/bliki/ValueObject.html](http://martinfowler.com/bliki/ValueObject.html)

I usually find there are several value objects for every entity
[https://dddsamplenet.codeplex.com/wikipage?title=DDD%20build...](https://dddsamplenet.codeplex.com/wikipage?title=DDD%20building%20blocks%20in%20DDDSample.Net)

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ExpiredLink
'Value Object' and 'Immutable Object' are a contradiction in terms.
Immutability refers to values, not 'objects'.

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benjiweber
Not sure what you are getting at. I assume you are using a specific definition
of these terms from a particular domain?

Immutable is just a word that means unchanging, as in "immutable laws of
nature". . Consequently Objects can be immutable if they cannot change after
creation. This seems a pretty commonly held view
[http://en.wikipedia.org/wiki/Immutable_object](http://en.wikipedia.org/wiki/Immutable_object)

How would you define Objects and Values?

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noblethrasher
An object has state by definition.

More to the point, an object has agency: It gets to decide how to interpret
messages sent to it (this is why we say that putting setters on classes turns
objects back into mere data structures [1]).

[http://www.devx.com/enterprise/the-vision-of-kay-and-
fieldin...](http://www.devx.com/enterprise/the-vision-of-kay-and-fielding-
growable-systems-that-last-for-decades.html) (right after the seventh
paragraph)

