it satisfies [ ` sized_range ` ](/w/cpp/ranges/sized_range "cpp/ranges/sized range") or [ ` forward_range ` ](/w/cpp/ranges/forward_range "cpp/ranges/forward range") .   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_empty&action=edit)  
[ cbegin  ](/w/cpp/ranges/view_interface/cbegin "cpp/ranges/view interface/cbegin") (C++23)  |  returns a constant iterator to the beginning of the range.   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_cbegin&action=edit)  
[ cend  ](/w/cpp/ranges/view_interface/cend "cpp/ranges/view interface/cend") (C++23)  |  returns a sentinel for the constant iterator of the range.   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_cend&action=edit)  
[ operator bool  ](/w/cpp/ranges/view_interface/operator_bool "cpp/ranges/view interface/operator bool") (C++20)  |  returns whether the derived view is not empty. Provided if  [ ranges::empty ](/w/cpp/ranges/empty "cpp/ranges/empty") is applicable to it.   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_operator_bool&action=edit)  
[ front  ](/w/cpp/ranges/view_interface/front "cpp/ranges/view interface/front") (C++20)  |  returns the first element in the derived view. Provided if it satisfies [ ` forward_range ` ](/w/cpp/ranges/forward_range "cpp/ranges/forward range") .   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_front&action=edit)  
[ back  ](/w/cpp/ranges/view_interface/back "cpp/ranges/view interface/back") (C++20)  |  returns the last element in the derived view. Provided if it satisfies [ ` bidirectional_range ` ](/w/cpp/ranges/bidirectional_range "cpp/ranges/bidirectional range") and [ ` common_range ` ](/w/cpp/ranges/common_range "cpp/ranges/common range") .   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_back&action=edit)  
[ operator[]  ](/w/cpp/ranges/view_interface/operator_at "cpp/ranges/view interface/operator at") (C++20)  |  returns the n  th  element in the derived view. Provided if it satisfies [ ` random_access_range ` ](/w/cpp/ranges/random_access_range "cpp/ranges/random access range") .   
(public member function of ` std::ranges::view_interface<D> ` )  [ [edit]
](https://en.cppreference.com/mwiki/index.php?title=Template:cpp/ranges/view_interface/dsc_operator_at&action=edit)  
  
###  [ [ edit
](/mwiki/index.php?title=cpp/ranges/transform_view&action=edit&section=2 "Edit
section: Deduction guides") ]  [ Deduction guides
](/w/cpp/ranges/transform_view/deduction_guides "cpp/ranges/transform
view/deduction guides")

###  [ [ edit
](/mwiki/index.php?title=cpp/ranges/transform_view&action=edit&section=3 "Edit
section: Nested classes") ]  Nested classes

[ _ iterator  _ ](/w/cpp/ranges/transform_view/iterator "cpp/ranges/transform view/iterator") (C++20)  |  the iterator type   
(  exposition-only member class template*  )  
---|---  
[ _ sentinel  _ ](/w/cpp/ranges/transform_view/sentinel "cpp/ranges/transform view/sentinel") (C++20)  |  the sentinel type   
(  exposition-only member class template*  )  
  
###  [ [ edit
](/mwiki/index.php?title=cpp/ranges/transform_view&action=edit&section=4 "Edit
section: Example") ]  Example

Run this code

    
    
    #include <algorithm>
    #include <cstdio>
    #include <iterator>
    #include <ranges>
    #include <string>
     
    char rot13a(const char x, const char a)
    {
        ret