As we can see the file reading function changes little - other than to have "async {...}" workflow wrapped round it and to make a call to the "ReadToEndAsync" function instead of "ReadToEnd".
No round tripping: there's no "round trip" support for iterative model changes, because the generated code is static.
不能往返：对于模型反复进行的更改不支持 “往返” 操作，这是因为所生成的代码是静态的。
3
For another, its powerful parsing abilities allow full round-tripping of code, so changes made to the source code are reflected nearly immediately in the graphical editor.