Board Thread:Lua Help/@comment-1370845-20160914214042/@comment-24473195-20160914222238

Two modules can access the data of a specific module in the module namespace, but can't access the changed data  of another module in the same page, unless they are added as parameters.

This is by design, because templates or even extensions that alter the output based on the data in the same page cause a lot of performance and usability issues, e.g. inside templates combines with those on a page. Another reason is that pages aren't meant to be used for calculations or complicated operations, and will cause issues if someone tries.