Correct usage(s) of const_cast<>

c++ const-cast
ereOn picture ereOn · Apr 20, 2010 · Viewed 17.9k times · Source

As a common rule, it is very often considered a bad practice to use const_cast<>() in C++ code as it reveals (most of the time) a flaw in the design.

While I totally agree with this, I however wonder what are the cases were using const_cast<>() is ok and the only solution.

Could you guys please give me some examples you know/you encountered ?

Thank you very much.

Answer

jk. picture jk. · Apr 20, 2010

it is pretty much designed to be only used with legacy APIs that are not const correct i.e. with a function you can't change that has non const interface but doesn't actually mutate anything on the interface

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