Class String

src/main/main.cpp:151–219

class String {
  private:
    char* _str;

  public:
    String(const char* str = "") {
        _str = strdup(str);
    }

    String(const String& other) {
        _str = strdup(other._str);
    }

    ~String() {
        free(_str);
    }

    String& operator=(const String& other) {
        if (this == &other) return *this;

        free(_str);
        _str = strdup(other._str);
        return *this;
    }

    const char* str() const {
        return _str;
    }

    bool operator==(const char* other) const {
        return strcmp(_str, other) == 0;
    }

    bool operator==(const String& other) const {
        return strcmp(_str, other._str) == 0;
    }

    String& operator<<(const char* tail) {
        size_t len = strlen(_str);
        _str = (char*)realloc(_str, len + strlen(tail) + 1);
        strcpy(_str + len, tail);
        return *this;
    }

    String& operator<<(String& tail) {
        return operator<<(tail._str);
    }

    String& operator<<(int n) {
        char buf[16];
        snprintf(buf, sizeof(buf), "%d", n);
        return operator<<(buf);
    }

    String& replace(char c, const char* rep) {
        const char* start = _str;
        const char* p;
        while ((p = strchr(start, c)) != NULL) {