On Fri, Nov 8, 2019 at 11:07 AM Ricky Teachey
__import__ already has a 'level' argument.
doh! maybe "context" is better, then.
Not without frame inspection to know what import statements are in the context manager's block.
I don't doubt you know what you're talking about, so this is a learning question: why couldn't you do it by simply adding an "inside_context_manager" flag, and producing an appropriate globals and locals based on the flag value?
Not thread-safe (we have a custom import lock to avoid this sort of problem) and the instant you start mucking with globals() and locals() you have (a) become a bit magical, and (b) made things extremely slow for PyPy. My opinion on this idea is while I appreciate the motivation behind it, this is proposing a lot of churn and change in Python to fix a single issue that only some people hit and most people learn to avoid the first time to realize what they have done. If it was a problem people ran into constantly throughout their life using Python then maybe I would personally be more receptive, but since it's a one-time mistake for vast majority of people I think I don't feel comfortable making every book on Python be outdated overnight over this. -Brett
this is really lame, but maybe like this:
class __import__:
def __enter__(self): self.inside_context_manager = True return None
def __exit__(self, *args): self.inside_context_manager = False
def __call__(self, name, globals=None, locals=None, fromlist=(), level=0, context=None): am_i_outside_context_manager = not self.inside_context_manager if am_i_outside_context_manager: do_normal_import(name, globals, locals, fromlist, level) else: # inside context manager if context is None: raise ValueError("invalid import context") cglobals = contextualized_globals(globals, context) clocals = contextualized_locals(locals, context) do_special_import(name, cglobals, clocals, fromlist, level)