docs: private Map<String, Macro> parseMacroDefinitions(List<String> defines) {
      final Map<String, Macro> result = new HashMap<>();
  
      for (String define : defines) {
        if (define.isEmpty()) {
          continue;
        }
  
        final String defineString = "#define " + define;
  
        LOG.debug("parsing external macro: '{}'", defineString);
        final Macro macro = parseMacroDefinition(defineString);
  
        if (macro != null) {
          if (LOG.isDebugEnabled()) {
            LOG.debug("storing external macro: '{}'", macro);
          }
          result.put(macro.name, macro);
        }
      }
      return result;
    }