c++ - Do I need to write the `const` keyword when passing a `const_iterator` as argument? - 


static void myclassmethod(           std::list<aclass>                 & anobject,     const std::list<aclass>::const_iterator & beginningpoint);

in code, i'm passing const_iterator of const stl object. feels 1 of constantnesses redundant.

how differ if remove const keyword, or if change const_iterator iterator?

std::list<aclass>::iterator&

you can change value through iterator , can change iterator points outside function.

std::list<aclass>::const_iterator&

you can't change value through iterator can change iterator points outside function.

const std::list<aclass>::iterator&

you can change value through iterator can't change iterator points outside function.

const std::list<aclass>::const_iterator&

you can't change value through iterator , can't change iterator points outside function.

take note iterators passed reference. if passed value, first const wouldn't matter much. because changing position of iterator effect local copy.


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