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A comment on The Time Needed to Write “Effective Modern C++”. Parent comment

Re:The Time Needed to Write “Effective Modern C++” by coliveira on Thursday April 23, 2015 @09:24AM (#9426463)
Except that it doesn't. Thanks to const_cast, you can take away constness from pointers, so where does your "guarantee" comes from?
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Re:The Time Needed to Write “Effective Modern C++” by netheril96 on Thursday April 23, 2015 @10:32AM (#9426918)
The guarantee is not against a malicious agent, but a reasonable programmer who may make mistakes.
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Re:The Time Needed to Write “Effective Modern C++” by detrino on Thursday April 23, 2015 @06:15PM (#9430240)
A function may not reliably cast a pointer-to-const-T to a pointer-to-T because T may actually be immutable, in which case modifying it would be UB. Like all casts, const_cast exists as an escape hatch in the type system for when you know that what you are doing is safe, even if the compiler can't prove it.
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