variables in expressjs views
Have you looked at dynamichelpers?
From the website:
app.dynamicHelpers(obj)
Registers dynamic view helpers. Dynamic view helpers are simply functions which accept req, res, and are evaluated against the Server instance before a view is rendered. The return value of this function becomes the local variable it is associated with.
app.dynamicHelpers({ session: function(req, res){ return req.session; }});
Most of the times I like to make it a function instead. This way it will be only called when you call the function in your views.