Indirect recursion only working with a breakpoint inserted

[jzoller]

Maybe someone can find what I'm doing incorrectly...

I'm doing a fairly literal port of json_parse.js from Douglas Crockford. It's an indirect recursive descent parser that uses a global to track where it's at in the JSON string that it's parsing. Essentially, value() calls object(). object() may then call value(), and so on. Works great... as long as my value.vi has a breakpoint inserted at the beginning. Take the breakpoint out, and the vi doesn't... really seem to execute. Or it does, but unpredictably.

Does anyone have any insight into what might be going on here? The code was crashing with an access violation. I spoke with an AE, and he said my top level VI was corrupted. Replacing the LV native globals with an LV2 global fixed the crash, but hasn't fixed the execution issue.

Code's attached, if anyone has any insight. Parse.vi is the top level. (Sorry, haven't had a chance to implement array() yet...)

Thanks,

Joe Z.

json indirect recursion.zip

Edited August 23, 2012 by jzoller

[Ton Plomp]

I saw one possible race condition in 'value'.

There was no data-dependency between 'white' and 'global' (white calls global internally).

Adding that fixed it it on my PC.

Ton

[jzoller]

Thanks Ton! I'll scrub the code for other possible race conditions as well.

Joe Z.

[Ton Plomp]

Have you ever looked at the 'Variant Probe/XControl'?

Here's the output plotted (on my comma seperated computer):

Ton

[jzoller]

It looks useful. My work currently doesn't allow me to get to the mirrors that carry the OpenG tools, so I'll check it out later tonight.

[Ton Plomp]

Hi Joe,

your code looks interesting! Any thought on uploading it to the CR?

Ton

[jzoller]

Ton,

There are potential licensing issues on this version. I'll be re-implementing (without globals) for an open source version... or anyone else is welcome to, if they wish.

Joe Z.