Build error with a comment just before the end of a grammar file

Hi guys! I’m afraid I’ve found a bug.

Last lines in grammar.ne:

...
_ -> %__:?     {% nuller %}
# --- //terminals ---

Build error (I’m using nearley-template btw):

[build] C:\new_projects\extensions\elm-ast\node_modules\nearley\lib\compile.js:25
        for (var i = 0; i < structure.length; i++) {
                                      ^

TypeError: Cannot read property 'length' of undefined
    at Compile (C:\new_projects\extensions\elm-ast\node_modules\nearley\lib\compile.js:25:39)
    at StreamWrapper.<anonymous> (C:\new_projects\extensions\elm-ast\node_modules\nearley\bin\nearleyc.js:57:17)
    at emitNone (events.js:110:20)
    at StreamWrapper.emit (events.js:207:7)
    at finishMaybe (_stream_writable.js:604:14)
    at endWritable (_stream_writable.js:612:3)
    at StreamWrapper.Writable.end (_stream_writable.js:563:5)
    at ReadStream.onend (_stream_readable.js:595:10)
    at Object.onceWrapper (events.js:312:30)
    at emitNone (events.js:110:20)
[build] [nodemon] app crashed - waiting for file changes before starting...

When I delete that last comment from grammar.ne, everything works.

My SW:

• node -v => v8.8.1
• npm -v => 5.6.0
• nearleyc -v => 2.11.1
• Windows 10

---

Very nice project, I’ve just found it today and I am trying to write parser for Elm, thanks 😃

[MartinKavik]

@tjvr No, it’s low prio. You can leave it to me, I’ll try to send PR, thanks 😃

[kach]

\n is how you tell nearley that you are done with the comment. In any case, I think all files should be \n-terminated. If you cat a non-newline-terminated file, it messes up your prompt! (You can configure your editor to do \n-terminate if it doesn’t already.)