The code in ex9_43.cpp may confuse the readers.

[jimages]

Hi,

Considering the situation where many newbie, i.e. me :) , will refer to the repo. They may feel confused when they read string const& oldVal, string const& newVal in ex9_44 and ex9_43 for the the book only mentions the const string &foo Which is the same case for the string{ cur, cur + oldVal.size() }.

I think we should add some notes for readability or make some changes.