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v0.5.1
v0.5.1
https://github.com/python/cpython
Tip revision: 74f4bd53e03ded8408bcc2de67cf0f5a4ac5b1a1 authored by Barry Warsaw on 23 February 2012, 15:59:38 UTC
Bump some more copyright years (as per PEP 101), since this is the first
Bump some more copyright years (as per PEP 101), since this is the first
Tip revision: 74f4bd5
knee.py
"""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__
# 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 = pname.rfind('.')
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 = name.find('.')
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 = tail.find('.')
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 = name.rfind('.')
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