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0 pointsnivertech14y ago0 comments

Erlang:

    X = 5.
    X2 = X+1.

C++:

    const int x = 5;
    const int x2 = x + 1.

My C++ style use const modifiers extensively. Likewise you can use final in Java.

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3 comments · 1 top-level

dan0014y ago· 2 in thread

const_cast and mutable, and gone is any kind of verification.

saurik14y ago

That your code uses neither is trivially verified with grep. Are you saying your issues would be solved if someone added a ten-line patch to gcc for -Wconst-cast (that provided a waning, obiously upgradable to an error, if you used const_cast; as in, similar to -Wold-style-cast)?

dan0014y ago

You really can't express immutability and pureness in C++, because you can still modify global variables and do any kind of IO everywhere, regardless of const.

const_cast isn't the big issue, because there's also unsafePerformIO in Haskell. For both you could say, that they shouldn't be used, that it's bad programming practice to use them.

The point is, even if you follow good programming practices in C++, you can't express them and your compiler can't help you in the verification, if you're really following them.

That doesn't might seem like a big thing, it's also not related to your smartness, because it mostly depends on the size and complexity of your system.

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