In article
<Pine.SOL.3.95q.971213225240.2846A-100000@somerville.math.uwaterloo.ca>,
Sunil Puri <spuri@undergrad.math.uwaterloo.ca> wrote:

> What is the mutable keyword used for?

A data member of a class that is declared mutable can be modified even for
a const instance of the class (during a const member method).

This is helpful for a class that holds data such as a cache.  A const
method may update the cache, even though there is no logical or conceptual
change to the object.  Thus the cache should be mutable.

-Howard
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It specifies that an instance variable can be modified when the object is
const, such as from within a const member function.

Stephen A. Ecker
secker@coredcs.com

Sunil Puri wrote in message ...
>What is the mutable keyword used for?
>
>Sunil Puri
>spuri@undergrad.math.uwaterloo.ca
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What is the mutable keyword used for?

Sunil Puri
spuri@undergrad.math.uwaterloo.ca
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