For example,
std::string_view strv{ "Hello" };
strv.remove_prefix(1);
The original string should be "Hello".
I tried using strv.data() and std::string str(strv.begin(), strv.end());
I can only get "ello" instead of "Hello".
2 Answers
I only found two methods right now.
use a variable(e.g.
string str) to store original string then use use string_view. When you need the original string, usestr.use a variable(e.g.
int removed_len) to record the length of removed prefixes. Then when you need the original stringstrv.data() - removed_lenis the start place of the original string.
1 Comment
Community
As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center.
The "Hello" you use to construct strv is your original string. However, you never actually instantiate that string, making it a prvalue. If you want to keep a copy of your original string, try something like:
std::string str{"Hello"};
std::string_view strv{str};
strv.remove_prefix(1);
str will hold your original string.
1 Comment
T.Chang
Is it possible to find an original anonymous string?
strv.remove_prefix(1), why would you expect anything other than "ello"?data()member returns a pointer to the first element of the view, not to the first element of the original string. Same goes for the iterators. The reason is that a view is like a window open on an actual container, not the container itself.strv.data() - 1? but it is now outside of the view...strv.data() - 1?datapoints into an array to a position wheredata() - 1is still inside that same array. AFAIK the pointer arithmetic rules say that is okay.