Namespaces/introspection: collecting sql strings for validation

[Peter Otten]

Martin Drautzburg wrote:

> > def SQL(sql, checked=set()):
> >     if sql in checked:
> >         return True
> >     if not valid_sql(sql): raise ValueError
> >     checked.add(sql)
> >     return sql
> 
> No this does not do the trick. I will not be able to validate an sql
> statement bofore I run over the piece of code that uses it. Or I would
> have to define all my sql = SQL stuff on module level, isn't id. I
> mean, the problem is: when are those sql = SQL statement really
> ececuted?

Let's see:

>>> def SQL(sql):
...     print sql
...
>>> a = SQL("module")
module # that one was obvious
>>> class A:
...     b = SQL("class")
...     def method(self, c=SQL("default arg")):
...             d = SQL("method")
...
class # ha, class statements are executed, too...
default arg # ...as are default arguments

Peter