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- """An Python re-implementation of hierarchical module import.
-
- This code is intended to be read, not executed. However, it does work
- -- all you need to do to enable it is "import knee".
-
- (The name is a pun on the klunkier predecessor of this module, "ni".)
-
- """
-
- import sys, imp, __builtin__, string
-
-
- # Replacement for __import__()
- def import_hook(name, globals=None, locals=None, fromlist=None):
- parent = determine_parent(globals)
- q, tail = find_head_package(parent, name)
- m = load_tail(q, tail)
- if not fromlist:
- return q
- if hasattr(m, "__path__"):
- ensure_fromlist(m, fromlist)
- return m
-
- def determine_parent(globals):
- if not globals or not globals.has_key("__name__"):
- return None
- pname = globals['__name__']
- if globals.has_key("__path__"):
- parent = sys.modules[pname]
- assert globals is parent.__dict__
- return parent
- if '.' in pname:
- i = string.rfind(pname, '.')
- pname = pname[:i]
- parent = sys.modules[pname]
- assert parent.__name__ == pname
- return parent
- return None
-
- def find_head_package(parent, name):
- if '.' in name:
- i = string.find(name, '.')
- head = name[:i]
- tail = name[i+1:]
- else:
- head = name
- tail = ""
- if parent:
- qname = "%s.%s" % (parent.__name__, head)
- else:
- qname = head
- q = import_module(head, qname, parent)
- if q: return q, tail
- if parent:
- qname = head
- parent = None
- q = import_module(head, qname, parent)
- if q: return q, tail
- raise ImportError, "No module named " + qname
-
- def load_tail(q, tail):
- m = q
- while tail:
- i = string.find(tail, '.')
- if i < 0: i = len(tail)
- head, tail = tail[:i], tail[i+1:]
- mname = "%s.%s" % (m.__name__, head)
- m = import_module(head, mname, m)
- if not m:
- raise ImportError, "No module named " + mname
- return m
-
- def ensure_fromlist(m, fromlist, recursive=0):
- for sub in fromlist:
- if sub == "*":
- if not recursive:
- try:
- all = m.__all__
- except AttributeError:
- pass
- else:
- ensure_fromlist(m, all, 1)
- continue
- if sub != "*" and not hasattr(m, sub):
- subname = "%s.%s" % (m.__name__, sub)
- submod = import_module(sub, subname, m)
- if not submod:
- raise ImportError, "No module named " + subname
-
- def import_module(partname, fqname, parent):
- try:
- return sys.modules[fqname]
- except KeyError:
- pass
- try:
- fp, pathname, stuff = imp.find_module(partname,
- parent and parent.__path__)
- except ImportError:
- return None
- try:
- m = imp.load_module(fqname, fp, pathname, stuff)
- finally:
- if fp: fp.close()
- if parent:
- setattr(parent, partname, m)
- return m
-
-
- # Replacement for reload()
- def reload_hook(module):
- name = module.__name__
- if '.' not in name:
- return import_module(name, name, None)
- i = string.rfind(name, '.')
- pname = name[:i]
- parent = sys.modules[pname]
- return import_module(name[i+1:], name, parent)
-
-
- # Save the original hooks
- original_import = __builtin__.__import__
- original_reload = __builtin__.reload
-
- # Now install our hooks
- __builtin__.__import__ = import_hook
- __builtin__.reload = reload_hook
-