G2 Events: Order of Modules

Does any one know if the order in which modules listening for an event are called is documented anywhere?

I.E. if Modules "A" and "B" are both listening for Event "Z", presumably they will have to be run one after the other and the question is whether how this is determined is documented.

I suppose I could try to root through the core files to try to figure it out.

Thanks

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