docs: public boolean addDef(String sec, String key, String value) {
          Assertion ast = new Assertion();
          ast.key = key;
          ast.value = value;
  
          if (ast.value.equals("")) {
              return false;
          }
  
          if (sec.equals("r") || sec.equals("p")) {
              ast.tokens = ast.value.split(", ");
              for (int i = 0; i < ast.tokens.length; i ++) {
                  ast.tokens[i] = key + "_" + ast.tokens[i];
              }
          } else {
              ast.value = Util.removeComments(Util.escapeAssertion(ast.value));
          }
  
          if (!model.containsKey(sec)) {
              model.put(sec, new HashMap<>());
          }
  
          model.get(sec).put(key, ast);
          return true;
      }