message: const_strlen without recursion
diff: @@ -54,11 +54,12 @@ namespace fc {
  const T& min( const T& a, const T& b ) { return a < b ? a: b; }
  constexpr size_t const_strlen(const char* str) {
  - if (*str == '\0') {
  - return 0;
  + size_t res = 0;
  + while (*str != '\0') {
  + ++res;
  + ++str;
  }
  -
  - return 1 + const_strlen(str+1);
  + return res;
  }
  