using names before they're defined

[davehowey at f2s.com]

Hiya

Could you just talk me through this... is it:

> schema = {'turbine1': {'class': 'Turbine',
>                        'upstream' : ('frobnicator2',),
>                        'downstream' : () # nothing,
>                        },
>           'frobnicator2' : {'class' : 'Frobnicator',
>                             'upstream' : (),
>                             'downstream' : ('frobnicator2',),
>                            },
>          }
>

ok, so schema is a dictionary of different components, defining what
class they are and what they're connected to.

> def get_class_by_name(name):
>   return globals()[name]

what does this function do exactly?

> def chain_from_schema(schema):
>   objects = {}   # so objects is our list of objects ?
>   for name, desc in schema:   # can you step through a dictionary like this?
>      klass =  get_class_by_name(desc['class'])   # does this create an object called klass?
>      objects[name] = klass()


sorry for being dim..
Dave