public ScriptEnvironment<T> withDeclarations(List<Decl> others) {
    return new ScriptEnvironment<>(concat(declarations, others), clazz, root);
  }
Returns a copy of this environment with a list of variable declarations appended to the global environment.
planetiler-custommap/src/main/java/com/onthegomap/planetiler/custommap/expression/ScriptEnvironment.java