Range based for null terminated string

range-based-for-null-terminated-string.cpp

#include <iostream>
#include <string>

template<class Char>
class ForEachNullTreminatedStringIterator {
    using ThisClass = ForEachNullTreminatedStringIterator;

public:
    ForEachNullTreminatedStringIterator() : p{} {}
    ForEachNullTreminatedStringIterator(Char* p) : p{p} {}

    Char& operator *() const {
        return *p;
    }

    ThisClass& operator ++ () {
        next();
        return *this;
    }

    bool operator == (const ThisClass& v) const {
        if(good() || v.good()) {
            return false;
        }
        return true;
    }

    bool operator != (const ThisClass& v) const {
        return ! (*this == v);
    }

protected:
    bool good() const {
        return p != nullptr;
    }

    void next() {
        if(good()) {
            ++p;
            if(0 == *p) {
                p = nullptr;
            }
        }
    }

    Char* p;
};


template<class Char>
class ForEachNullTreminatedString {
public:
    using iterator  = ForEachNullTreminatedStringIterator<Char>;

public:
    explicit ForEachNullTreminatedString(iterator str) : itBegin { str } {}
    iterator begin() const { return itBegin; }
    iterator end() const { return iterator {}; }

private:
    iterator    itBegin;
};


inline ForEachNullTreminatedString<char> foreach(char* str) {
    return ForEachNullTreminatedString<char> {str};
}

inline ForEachNullTreminatedString<char> foreach(std::string& str) {
    return foreach(&str[0]);
}

inline ForEachNullTreminatedString<const char> foreach(const char* str) {
    return ForEachNullTreminatedString<const char> {str};
}

inline ForEachNullTreminatedString<const char> foreach(const std::string& str) {
    return foreach(&str[0]);
}


int main() {
    {
        const char str[] = "TEST STRING";
        for(const char& c : foreach(str)) {
            std::cout << c;
        }
        std::cout << std::endl;
    }

    {
        char str[] = "TEST STRING";

        for(char& c : foreach(str)) {
            if('T' == c) {
                c = '+';
            }
        }

        std::cout << str << std::endl;
    }

    {
        const auto str = std::string("TEST STRING");
        for(const char& c : foreach(str)) {
            std::cout << c;
        }
        std::cout << std::endl;
    }

    {
        auto str = std::string("TEST STRING");

        for(char& c : foreach(str)) {
            if('T' == c) {
                c = '+';
            }
        }

        std::cout << str << std::endl;
    }
}

https://ideone.com/YQcReL