我见过很多人从一个模块中提取所有类的例子,通常是这样的:
# foo.py
class Foo:
pass
# test.py
import inspect
import foo
for name, obj in inspect.getmembers(foo):
if inspect.isclass(obj):
print obj
太棒了。
但是我不知道如何从当前模块中获得所有的类。
# foo.py
import inspect
class Foo:
pass
def print_classes():
for name, obj in inspect.getmembers(???): # what do I do here?
if inspect.isclass(obj):
print obj
# test.py
import foo
foo.print_classes()
这可能是非常明显的事情,但我还没有找到任何东西。有人能帮帮我吗?
进入Python解释器。输入help ('module_name'),然后按Enter。
例如help('os')。
在这里,我把输出的一部分粘贴在下面:
class statvfs_result(__builtin__.object)
| statvfs_result: Result from statvfs or fstatvfs.
|
| This object may be accessed either as a tuple of
| (bsize, frsize, blocks, bfree, bavail, files, ffree, favail, flag, namemax),
| or via the attributes f_bsize, f_frsize, f_blocks, f_bfree, and so on.
|
| See os.statvfs for more information.
|
| Methods defined here:
|
| __add__(...)
| x.__add__(y) <==> x+y
|
| __contains__(...)
| x.__contains__(y) <==> y in x
如果你想拥有所有属于当前模块的类,你可以使用这个:
import sys, inspect
def print_classes():
is_class_member = lambda member: inspect.isclass(member) and member.__module__ == __name__
clsmembers = inspect.getmembers(sys.modules[__name__], is_class_member)
如果你使用Nadia的答案,你在你的模块上导入其他类,这些类也将被导入。
这就是为什么成员。__module__ == __name__被添加到is_class_member上使用的谓词中。这个语句检查类是否真的属于模块。
谓词是返回布尔值的函数(可调用)。
我可以从dir内置的加上getattr中得到我需要的一切。
# Works on pretty much everything, but be mindful that
# you get lists of strings back
print dir(myproject)
print dir(myproject.mymodule)
print dir(myproject.mymodule.myfile)
print dir(myproject.mymodule.myfile.myclass)
# But, the string names can be resolved with getattr, (as seen below)
不过,它看起来确实像一个毛球:
def list_supported_platforms():
"""
List supported platforms (to match sys.platform)
@Retirms:
list str: platform names
"""
return list(itertools.chain(
*list(
# Get the class's constant
getattr(
# Get the module's first class, which we wrote
getattr(
# Get the module
getattr(platforms, item),
dir(
getattr(platforms, item)
)[0]
),
'SYS_PLATFORMS'
)
# For each include in platforms/__init__.py
for item in dir(platforms)
# Ignore magic, ourselves (index.py) and a base class.
if not item.startswith('__') and item not in ['index', 'base']
)
))