c++ - Why make a parameter const if you're going to do const_cast? -

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there linked list example trying append node. part of code:

void append(listelement<t> const* ptr, t const& datum) {     listelement<t>* temp = const_cast<listelement<t>*>(ptr);     // ... }

what point in making ptr pointer const if you're going cast away? ptr isn't used anywhere in function, temp, wouldn't better make pointer non-const people know object might modified?

is there reason make parameter const , const_cast'ing away in body instead of making non-const?

what point in making ptr pointer const if you're going cast away?

none.

it breaks function contract , example of getting lost in code design.

to illustrate, this

  • a: hey, can read object, read.
  • b: okay, give me it, i'm going read it.
  • b: writes on it

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