[boost] pass data between two layers (req. of patterns)

From: Oliver.Kowalke_at_[hidden]
Date: 2007-09-19 03:45:39

Hello,
what would be a good practice to pass data between two layers. The upper
layer invokes functionality of the lower layer and vice versa.
One solution could be to implement the two layers as singletons which
memebr functions implement the provided functionalities of the layer.
But this would result in unreadable code.
Do you have better suggestions (patterns)?
Regards, Oliver