text: #ifndef NHL_MEM_H_
  #define NHL_MEM_H_
  
  /* Maximum length (without the terminating null) of a string representation of an int.
   * See, e.g., https://stackoverflow.com/a/32871108 */
  #define NHL_INTSTR_LEN ((CHAR_BIT * sizeof(int) - 1) * 10/33 + 2)
  
  /* ANSI C compatible version of strdup(). Input must be null-terminated. Release with free(). */
  char *nhl_copy_string(const char *str);
  
  #endif /* NHL_MEM_H_ */
  