disable sorting

[ajoslin103]

I want to use this library to read already written binary files, porting in c/c++ structs -- but it's sorting the schema and that is totally screwing things up

Please consider an option to disable the schema sorting!!

[phretaddin]

The keys are sorted on this line: https://github.com/phretaddin/schemapack/blob/master/schemapack.js#L265

The reason schemas are sorted is because iteration order of objects in JavaScript is not guaranteed. For example, if you have the same exact schema on the client and server. It's possible (although not generally likely) that it could be iterated in a different order on both the client and server, which would cause the wrong object to be decoded.

For this reason, the schemas are sorted by alphabetical order and turned in to an array to guarantee traversal order.

If you don't need this, then you can just comment out that line I posted at the top.

[ajoslin103]

I submitted a pull-request with a change to make it a selectable option -- I didn't think of the iteration order... So the fact that my test worked when only decoding packed data was essentially luck, eh? Hrmmm....

So if one were to do un-sorted one would have to also include an array of fields to specify their order... That would have to prefix the data, and would be a breaking change as you don't enforce a version # at the head of the data-block I think...

[phretaddin]

Yeah, just luck. Most of the time it works (especially with newer browsers), but you can run in to cases where the iteration order is different, so sorting or something has to be done first.

Yeah, prefixing the data would be a breaking change. I tried to think of an alternative to alphabetical sorting but didn't come up with much.

[ajoslin103]

ok, so reject my pull-request and give some thought to my suggestion at the end of the fixed-length elements issue.

thx