Wednesday, May 6, 2009

const nonref variable - non-trivial

Reading the c++ FAQ 18.10, I got the impression that most const variables are ptr or ref.

const nonref primitive is like a java constant or java immutable.

Q: are there const nonref class object? Are they immutable?
A: Yes according to http://www.learncpp.com/cpp-tutorial/810-const-class-objects-and-member-functions/

Once a const class object has been initialized via constructor, any attempt to modify the member variables of the object is disallowed, as it would violate the constness of the object.

Just like the built-in data types (int, double, char, etc…), class objects can be made const by using the const keyword.

Q: can you cast away its constness?
A: very tricky.  See effC++ and the IBM arcitlce.  Short answer is no.

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