Re: about scoping in modules

*To*: mathgroup at smc.vnet.net*Subject*: [mg85797] Re: about scoping in modules*From*: Albert Retey <awnl at arcor.net>*Date*: Fri, 22 Feb 2008 07:24:35 -0500 (EST)*References*: <fpkvqk$hrr$1@smc.vnet.net>

Hi Peter > in the next two modules I would like that the inner module uses a variable from the outer module. > mfb[oneObj_] := Module[{ttmp = oneObj},AppendTo[ global2mfb, ttmp]] > mfa[e_] := Module[{global2mfb = e, t = 3},mfb[t] ] > mfa[{2,3}] gives a message that global2mfb is not a variable with a value, so it can not be changed. > It means I do not understand the concept of module in Mathematica. My questions are: > 1. why does it go wrong? Because of the difference between lexical and dynamical scoping. This is explained in the documentation. In version 6 you can copy the following line to the documentation center to point it to a useful starting point about the topic: tutorial/BlocksComparedWithModules > 2. how can I realize what I want? use Block instead of Module in the definition of mfa and it will do what I think you try to achieve... hth, albert