--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Lib/inspect.py Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,959 @@
+# -*- coding: iso-8859-1 -*-
+"""Get useful information from live Python objects.
+
+This module encapsulates the interface provided by the internal special
+attributes (func_*, co_*, im_*, tb_*, etc.) in a friendlier fashion.
+It also provides some help for examining source code and class layout.
+
+Here are some of the useful functions provided by this module:
+
+ ismodule(), isclass(), ismethod(), isfunction(), isgeneratorfunction(),
+ isgenerator(), istraceback(), isframe(), iscode(), isbuiltin(),
+ isroutine() - check object types
+ getmembers() - get members of an object that satisfy a given condition
+
+ getfile(), getsourcefile(), getsource() - find an object's source code
+ getdoc(), getcomments() - get documentation on an object
+ getmodule() - determine the module that an object came from
+ getclasstree() - arrange classes so as to represent their hierarchy
+
+ getargspec(), getargvalues() - get info about function arguments
+ formatargspec(), formatargvalues() - format an argument spec
+ getouterframes(), getinnerframes() - get info about frames
+ currentframe() - get the current stack frame
+ stack(), trace() - get info about frames on the stack or in a traceback
+"""
+
+# This module is in the public domain. No warranties.
+
+__author__ = 'Ka-Ping Yee <ping@lfw.org>'
+__date__ = '1 Jan 2001'
+
+import sys
+import os
+import types
+import string
+import re
+import dis
+import imp
+import tokenize
+import linecache
+from operator import attrgetter
+from collections import namedtuple
+
+# These constants are from Include/code.h.
+CO_OPTIMIZED, CO_NEWLOCALS, CO_VARARGS, CO_VARKEYWORDS = 0x1, 0x2, 0x4, 0x8
+CO_NESTED, CO_GENERATOR, CO_NOFREE = 0x10, 0x20, 0x40
+# See Include/object.h
+TPFLAGS_IS_ABSTRACT = 1 << 20
+
+# ----------------------------------------------------------- type-checking
+def ismodule(object):
+ """Return true if the object is a module.
+
+ Module objects provide these attributes:
+ __doc__ documentation string
+ __file__ filename (missing for built-in modules)"""
+ return isinstance(object, types.ModuleType)
+
+def isclass(object):
+ """Return true if the object is a class.
+
+ Class objects provide these attributes:
+ __doc__ documentation string
+ __module__ name of module in which this class was defined"""
+ return isinstance(object, types.ClassType) or hasattr(object, '__bases__')
+
+def ismethod(object):
+ """Return true if the object is an instance method.
+
+ Instance method objects provide these attributes:
+ __doc__ documentation string
+ __name__ name with which this method was defined
+ im_class class object in which this method belongs
+ im_func function object containing implementation of method
+ im_self instance to which this method is bound, or None"""
+ return isinstance(object, types.MethodType)
+
+def ismethoddescriptor(object):
+ """Return true if the object is a method descriptor.
+
+ But not if ismethod() or isclass() or isfunction() are true.
+
+ This is new in Python 2.2, and, for example, is true of int.__add__.
+ An object passing this test has a __get__ attribute but not a __set__
+ attribute, but beyond that the set of attributes varies. __name__ is
+ usually sensible, and __doc__ often is.
+
+ Methods implemented via descriptors that also pass one of the other
+ tests return false from the ismethoddescriptor() test, simply because
+ the other tests promise more -- you can, e.g., count on having the
+ im_func attribute (etc) when an object passes ismethod()."""
+ return (hasattr(object, "__get__")
+ and not hasattr(object, "__set__") # else it's a data descriptor
+ and not ismethod(object) # mutual exclusion
+ and not isfunction(object)
+ and not isclass(object))
+
+def isdatadescriptor(object):
+ """Return true if the object is a data descriptor.
+
+ Data descriptors have both a __get__ and a __set__ attribute. Examples are
+ properties (defined in Python) and getsets and members (defined in C).
+ Typically, data descriptors will also have __name__ and __doc__ attributes
+ (properties, getsets, and members have both of these attributes), but this
+ is not guaranteed."""
+ return (hasattr(object, "__set__") and hasattr(object, "__get__"))
+
+if hasattr(types, 'MemberDescriptorType'):
+ # CPython and equivalent
+ def ismemberdescriptor(object):
+ """Return true if the object is a member descriptor.
+
+ Member descriptors are specialized descriptors defined in extension
+ modules."""
+ return isinstance(object, types.MemberDescriptorType)
+else:
+ # Other implementations
+ def ismemberdescriptor(object):
+ """Return true if the object is a member descriptor.
+
+ Member descriptors are specialized descriptors defined in extension
+ modules."""
+ return False
+
+if hasattr(types, 'GetSetDescriptorType'):
+ # CPython and equivalent
+ def isgetsetdescriptor(object):
+ """Return true if the object is a getset descriptor.
+
+ getset descriptors are specialized descriptors defined in extension
+ modules."""
+ return isinstance(object, types.GetSetDescriptorType)
+else:
+ # Other implementations
+ def isgetsetdescriptor(object):
+ """Return true if the object is a getset descriptor.
+
+ getset descriptors are specialized descriptors defined in extension
+ modules."""
+ return False
+
+def isfunction(object):
+ """Return true if the object is a user-defined function.
+
+ Function objects provide these attributes:
+ __doc__ documentation string
+ __name__ name with which this function was defined
+ func_code code object containing compiled function bytecode
+ func_defaults tuple of any default values for arguments
+ func_doc (same as __doc__)
+ func_globals global namespace in which this function was defined
+ func_name (same as __name__)"""
+ return isinstance(object, types.FunctionType)
+
+def isgeneratorfunction(object):
+ """Return true if the object is a user-defined generator function.
+
+ Generator function objects provides same attributes as functions.
+
+ See isfunction.__doc__ for attributes listing."""
+ if (isfunction(object) or ismethod(object)) and \
+ object.func_code.co_flags & CO_GENERATOR:
+ return True
+
+def isgenerator(object):
+ """Return true if the object is a generator.
+
+ Generator objects provide these attributes:
+ __iter__ defined to support interation over container
+ close raises a new GeneratorExit exception inside the
+ generator to terminate the iteration
+ gi_code code object
+ gi_frame frame object or possibly None once the generator has
+ been exhausted
+ gi_running set to 1 when generator is executing, 0 otherwise
+ next return the next item from the container
+ send resumes the generator and "sends" a value that becomes
+ the result of the current yield-expression
+ throw used to raise an exception inside the generator"""
+ return isinstance(object, types.GeneratorType)
+
+def istraceback(object):
+ """Return true if the object is a traceback.
+
+ Traceback objects provide these attributes:
+ tb_frame frame object at this level
+ tb_lasti index of last attempted instruction in bytecode
+ tb_lineno current line number in Python source code
+ tb_next next inner traceback object (called by this level)"""
+ return isinstance(object, types.TracebackType)
+
+def isframe(object):
+ """Return true if the object is a frame object.
+
+ Frame objects provide these attributes:
+ f_back next outer frame object (this frame's caller)
+ f_builtins built-in namespace seen by this frame
+ f_code code object being executed in this frame
+ f_exc_traceback traceback if raised in this frame, or None
+ f_exc_type exception type if raised in this frame, or None
+ f_exc_value exception value if raised in this frame, or None
+ f_globals global namespace seen by this frame
+ f_lasti index of last attempted instruction in bytecode
+ f_lineno current line number in Python source code
+ f_locals local namespace seen by this frame
+ f_restricted 0 or 1 if frame is in restricted execution mode
+ f_trace tracing function for this frame, or None"""
+ return isinstance(object, types.FrameType)
+
+def iscode(object):
+ """Return true if the object is a code object.
+
+ Code objects provide these attributes:
+ co_argcount number of arguments (not including * or ** args)
+ co_code string of raw compiled bytecode
+ co_consts tuple of constants used in the bytecode
+ co_filename name of file in which this code object was created
+ co_firstlineno number of first line in Python source code
+ co_flags bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg
+ co_lnotab encoded mapping of line numbers to bytecode indices
+ co_name name with which this code object was defined
+ co_names tuple of names of local variables
+ co_nlocals number of local variables
+ co_stacksize virtual machine stack space required
+ co_varnames tuple of names of arguments and local variables"""
+ return isinstance(object, types.CodeType)
+
+def isbuiltin(object):
+ """Return true if the object is a built-in function or method.
+
+ Built-in functions and methods provide these attributes:
+ __doc__ documentation string
+ __name__ original name of this function or method
+ __self__ instance to which a method is bound, or None"""
+ return isinstance(object, types.BuiltinFunctionType)
+
+def isroutine(object):
+ """Return true if the object is any kind of function or method."""
+ return (isbuiltin(object)
+ or isfunction(object)
+ or ismethod(object)
+ or ismethoddescriptor(object))
+
+def isgenerator(object):
+ """Return true if the object is a generator object."""
+ return isinstance(object, types.GeneratorType)
+
+def isabstract(object):
+ """Return true if the object is an abstract base class (ABC)."""
+ return isinstance(object, type) and object.__flags__ & TPFLAGS_IS_ABSTRACT
+
+def getmembers(object, predicate=None):
+ """Return all members of an object as (name, value) pairs sorted by name.
+ Optionally, only return members that satisfy a given predicate."""
+ results = []
+ for key in dir(object):
+ value = getattr(object, key)
+ if not predicate or predicate(value):
+ results.append((key, value))
+ results.sort()
+ return results
+
+Attribute = namedtuple('Attribute', 'name kind defining_class object')
+
+def classify_class_attrs(cls):
+ """Return list of attribute-descriptor tuples.
+
+ For each name in dir(cls), the return list contains a 4-tuple
+ with these elements:
+
+ 0. The name (a string).
+
+ 1. The kind of attribute this is, one of these strings:
+ 'class method' created via classmethod()
+ 'static method' created via staticmethod()
+ 'property' created via property()
+ 'method' any other flavor of method
+ 'data' not a method
+
+ 2. The class which defined this attribute (a class).
+
+ 3. The object as obtained directly from the defining class's
+ __dict__, not via getattr. This is especially important for
+ data attributes: C.data is just a data object, but
+ C.__dict__['data'] may be a data descriptor with additional
+ info, like a __doc__ string.
+ """
+
+ mro = getmro(cls)
+ names = dir(cls)
+ result = []
+ for name in names:
+ # Get the object associated with the name.
+ # Getting an obj from the __dict__ sometimes reveals more than
+ # using getattr. Static and class methods are dramatic examples.
+ if name in cls.__dict__:
+ obj = cls.__dict__[name]
+ else:
+ obj = getattr(cls, name)
+
+ # Figure out where it was defined.
+ homecls = getattr(obj, "__objclass__", None)
+ if homecls is None:
+ # search the dicts.
+ for base in mro:
+ if name in base.__dict__:
+ homecls = base
+ break
+
+ # Get the object again, in order to get it from the defining
+ # __dict__ instead of via getattr (if possible).
+ if homecls is not None and name in homecls.__dict__:
+ obj = homecls.__dict__[name]
+
+ # Also get the object via getattr.
+ obj_via_getattr = getattr(cls, name)
+
+ # Classify the object.
+ if isinstance(obj, staticmethod):
+ kind = "static method"
+ elif isinstance(obj, classmethod):
+ kind = "class method"
+ elif isinstance(obj, property):
+ kind = "property"
+ elif (ismethod(obj_via_getattr) or
+ ismethoddescriptor(obj_via_getattr)):
+ kind = "method"
+ else:
+ kind = "data"
+
+ result.append(Attribute(name, kind, homecls, obj))
+
+ return result
+
+# ----------------------------------------------------------- class helpers
+def _searchbases(cls, accum):
+ # Simulate the "classic class" search order.
+ if cls in accum:
+ return
+ accum.append(cls)
+ for base in cls.__bases__:
+ _searchbases(base, accum)
+
+def getmro(cls):
+ "Return tuple of base classes (including cls) in method resolution order."
+ if hasattr(cls, "__mro__"):
+ return cls.__mro__
+ else:
+ result = []
+ _searchbases(cls, result)
+ return tuple(result)
+
+# -------------------------------------------------- source code extraction
+def indentsize(line):
+ """Return the indent size, in spaces, at the start of a line of text."""
+ expline = string.expandtabs(line)
+ return len(expline) - len(string.lstrip(expline))
+
+def getdoc(object):
+ """Get the documentation string for an object.
+
+ All tabs are expanded to spaces. To clean up docstrings that are
+ indented to line up with blocks of code, any whitespace than can be
+ uniformly removed from the second line onwards is removed."""
+ try:
+ doc = object.__doc__
+ except AttributeError:
+ return None
+ if not isinstance(doc, types.StringTypes):
+ return None
+ return cleandoc(doc)
+
+def cleandoc(doc):
+ """Clean up indentation from docstrings.
+
+ Any whitespace that can be uniformly removed from the second line
+ onwards is removed."""
+ try:
+ lines = string.split(string.expandtabs(doc), '\n')
+ except UnicodeError:
+ return None
+ else:
+ # Find minimum indentation of any non-blank lines after first line.
+ margin = sys.maxint
+ for line in lines[1:]:
+ content = len(string.lstrip(line))
+ if content:
+ indent = len(line) - content
+ margin = min(margin, indent)
+ # Remove indentation.
+ if lines:
+ lines[0] = lines[0].lstrip()
+ if margin < sys.maxint:
+ for i in range(1, len(lines)): lines[i] = lines[i][margin:]
+ # Remove any trailing or leading blank lines.
+ while lines and not lines[-1]:
+ lines.pop()
+ while lines and not lines[0]:
+ lines.pop(0)
+ return string.join(lines, '\n')
+
+def getfile(object):
+ """Work out which source or compiled file an object was defined in."""
+ if ismodule(object):
+ if hasattr(object, '__file__'):
+ return object.__file__
+ raise TypeError('arg is a built-in module')
+ if isclass(object):
+ object = sys.modules.get(object.__module__)
+ if hasattr(object, '__file__'):
+ return object.__file__
+ raise TypeError('arg is a built-in class')
+ if ismethod(object):
+ object = object.im_func
+ if isfunction(object):
+ object = object.func_code
+ if istraceback(object):
+ object = object.tb_frame
+ if isframe(object):
+ object = object.f_code
+ if iscode(object):
+ return object.co_filename
+ raise TypeError('arg is not a module, class, method, '
+ 'function, traceback, frame, or code object')
+
+ModuleInfo = namedtuple('ModuleInfo', 'name suffix mode module_type')
+
+def getmoduleinfo(path):
+ """Get the module name, suffix, mode, and module type for a given file."""
+ filename = os.path.basename(path)
+ suffixes = map(lambda info:
+ (-len(info[0]), info[0], info[1], info[2]),
+ imp.get_suffixes())
+ suffixes.sort() # try longest suffixes first, in case they overlap
+ for neglen, suffix, mode, mtype in suffixes:
+ if filename[neglen:] == suffix:
+ return ModuleInfo(filename[:neglen], suffix, mode, mtype)
+
+def getmodulename(path):
+ """Return the module name for a given file, or None."""
+ info = getmoduleinfo(path)
+ if info: return info[0]
+
+def getsourcefile(object):
+ """Return the Python source file an object was defined in, if it exists."""
+ filename = getfile(object)
+ if string.lower(filename[-4:]) in ('.pyc', '.pyo'):
+ filename = filename[:-4] + '.py'
+ for suffix, mode, kind in imp.get_suffixes():
+ if 'b' in mode and string.lower(filename[-len(suffix):]) == suffix:
+ # Looks like a binary file. We want to only return a text file.
+ return None
+ if os.path.exists(filename):
+ return filename
+ # only return a non-existent filename if the module has a PEP 302 loader
+ if hasattr(getmodule(object, filename), '__loader__'):
+ return filename
+
+def getabsfile(object, _filename=None):
+ """Return an absolute path to the source or compiled file for an object.
+
+ The idea is for each object to have a unique origin, so this routine
+ normalizes the result as much as possible."""
+ if _filename is None:
+ _filename = getsourcefile(object) or getfile(object)
+ return os.path.normcase(os.path.abspath(_filename))
+
+modulesbyfile = {}
+_filesbymodname = {}
+
+def getmodule(object, _filename=None):
+ """Return the module an object was defined in, or None if not found."""
+ if ismodule(object):
+ return object
+ if hasattr(object, '__module__'):
+ return sys.modules.get(object.__module__)
+ # Try the filename to modulename cache
+ if _filename is not None and _filename in modulesbyfile:
+ return sys.modules.get(modulesbyfile[_filename])
+ # Try the cache again with the absolute file name
+ try:
+ file = getabsfile(object, _filename)
+ except TypeError:
+ return None
+ if file in modulesbyfile:
+ return sys.modules.get(modulesbyfile[file])
+ # Update the filename to module name cache and check yet again
+ # Copy sys.modules in order to cope with changes while iterating
+ for modname, module in sys.modules.items():
+ if ismodule(module) and hasattr(module, '__file__'):
+ f = module.__file__
+ if f == _filesbymodname.get(modname, None):
+ # Have already mapped this module, so skip it
+ continue
+ _filesbymodname[modname] = f
+ f = getabsfile(module)
+ # Always map to the name the module knows itself by
+ modulesbyfile[f] = modulesbyfile[
+ os.path.realpath(f)] = module.__name__
+ if file in modulesbyfile:
+ return sys.modules.get(modulesbyfile[file])
+ # Check the main module
+ main = sys.modules['__main__']
+ if not hasattr(object, '__name__'):
+ return None
+ if hasattr(main, object.__name__):
+ mainobject = getattr(main, object.__name__)
+ if mainobject is object:
+ return main
+ # Check builtins
+ builtin = sys.modules['__builtin__']
+ if hasattr(builtin, object.__name__):
+ builtinobject = getattr(builtin, object.__name__)
+ if builtinobject is object:
+ return builtin
+
+def findsource(object):
+ """Return the entire source file and starting line number for an object.
+
+ The argument may be a module, class, method, function, traceback, frame,
+ or code object. The source code is returned as a list of all the lines
+ in the file and the line number indexes a line in that list. An IOError
+ is raised if the source code cannot be retrieved."""
+ file = getsourcefile(object) or getfile(object)
+ module = getmodule(object, file)
+ if module:
+ lines = linecache.getlines(file, module.__dict__)
+ else:
+ lines = linecache.getlines(file)
+ if not lines:
+ raise IOError('could not get source code')
+
+ if ismodule(object):
+ return lines, 0
+
+ if isclass(object):
+ name = object.__name__
+ pat = re.compile(r'^(\s*)class\s*' + name + r'\b')
+ # make some effort to find the best matching class definition:
+ # use the one with the least indentation, which is the one
+ # that's most probably not inside a function definition.
+ candidates = []
+ for i in range(len(lines)):
+ match = pat.match(lines[i])
+ if match:
+ # if it's at toplevel, it's already the best one
+ if lines[i][0] == 'c':
+ return lines, i
+ # else add whitespace to candidate list
+ candidates.append((match.group(1), i))
+ if candidates:
+ # this will sort by whitespace, and by line number,
+ # less whitespace first
+ candidates.sort()
+ return lines, candidates[0][1]
+ else:
+ raise IOError('could not find class definition')
+
+ if ismethod(object):
+ object = object.im_func
+ if isfunction(object):
+ object = object.func_code
+ if istraceback(object):
+ object = object.tb_frame
+ if isframe(object):
+ object = object.f_code
+ if iscode(object):
+ if not hasattr(object, 'co_firstlineno'):
+ raise IOError('could not find function definition')
+ lnum = object.co_firstlineno - 1
+ pat = re.compile(r'^(\s*def\s)|(.*(?<!\w)lambda(:|\s))|^(\s*@)')
+ while lnum > 0:
+ if pat.match(lines[lnum]): break
+ lnum = lnum - 1
+ return lines, lnum
+ raise IOError('could not find code object')
+
+def getcomments(object):
+ """Get lines of comments immediately preceding an object's source code.
+
+ Returns None when source can't be found.
+ """
+ try:
+ lines, lnum = findsource(object)
+ except (IOError, TypeError):
+ return None
+
+ if ismodule(object):
+ # Look for a comment block at the top of the file.
+ start = 0
+ if lines and lines[0][:2] == '#!': start = 1
+ while start < len(lines) and string.strip(lines[start]) in ('', '#'):
+ start = start + 1
+ if start < len(lines) and lines[start][:1] == '#':
+ comments = []
+ end = start
+ while end < len(lines) and lines[end][:1] == '#':
+ comments.append(string.expandtabs(lines[end]))
+ end = end + 1
+ return string.join(comments, '')
+
+ # Look for a preceding block of comments at the same indentation.
+ elif lnum > 0:
+ indent = indentsize(lines[lnum])
+ end = lnum - 1
+ if end >= 0 and string.lstrip(lines[end])[:1] == '#' and \
+ indentsize(lines[end]) == indent:
+ comments = [string.lstrip(string.expandtabs(lines[end]))]
+ if end > 0:
+ end = end - 1
+ comment = string.lstrip(string.expandtabs(lines[end]))
+ while comment[:1] == '#' and indentsize(lines[end]) == indent:
+ comments[:0] = [comment]
+ end = end - 1
+ if end < 0: break
+ comment = string.lstrip(string.expandtabs(lines[end]))
+ while comments and string.strip(comments[0]) == '#':
+ comments[:1] = []
+ while comments and string.strip(comments[-1]) == '#':
+ comments[-1:] = []
+ return string.join(comments, '')
+
+class EndOfBlock(Exception): pass
+
+class BlockFinder:
+ """Provide a tokeneater() method to detect the end of a code block."""
+ def __init__(self):
+ self.indent = 0
+ self.islambda = False
+ self.started = False
+ self.passline = False
+ self.last = 1
+
+ def tokeneater(self, type, token, srow_scol, erow_ecol, line):
+ srow, scol = srow_scol
+ erow, ecol = erow_ecol
+ if not self.started:
+ # look for the first "def", "class" or "lambda"
+ if token in ("def", "class", "lambda"):
+ if token == "lambda":
+ self.islambda = True
+ self.started = True
+ self.passline = True # skip to the end of the line
+ elif type == tokenize.NEWLINE:
+ self.passline = False # stop skipping when a NEWLINE is seen
+ self.last = srow
+ if self.islambda: # lambdas always end at the first NEWLINE
+ raise EndOfBlock
+ elif self.passline:
+ pass
+ elif type == tokenize.INDENT:
+ self.indent = self.indent + 1
+ self.passline = True
+ elif type == tokenize.DEDENT:
+ self.indent = self.indent - 1
+ # the end of matching indent/dedent pairs end a block
+ # (note that this only works for "def"/"class" blocks,
+ # not e.g. for "if: else:" or "try: finally:" blocks)
+ if self.indent <= 0:
+ raise EndOfBlock
+ elif self.indent == 0 and type not in (tokenize.COMMENT, tokenize.NL):
+ # any other token on the same indentation level end the previous
+ # block as well, except the pseudo-tokens COMMENT and NL.
+ raise EndOfBlock
+
+def getblock(lines):
+ """Extract the block of code at the top of the given list of lines."""
+ blockfinder = BlockFinder()
+ try:
+ tokenize.tokenize(iter(lines).next, blockfinder.tokeneater)
+ except (EndOfBlock, IndentationError):
+ pass
+ return lines[:blockfinder.last]
+
+def getsourcelines(object):
+ """Return a list of source lines and starting line number for an object.
+
+ The argument may be a module, class, method, function, traceback, frame,
+ or code object. The source code is returned as a list of the lines
+ corresponding to the object and the line number indicates where in the
+ original source file the first line of code was found. An IOError is
+ raised if the source code cannot be retrieved."""
+ lines, lnum = findsource(object)
+
+ if ismodule(object): return lines, 0
+ else: return getblock(lines[lnum:]), lnum + 1
+
+def getsource(object):
+ """Return the text of the source code for an object.
+
+ The argument may be a module, class, method, function, traceback, frame,
+ or code object. The source code is returned as a single string. An
+ IOError is raised if the source code cannot be retrieved."""
+ lines, lnum = getsourcelines(object)
+ return string.join(lines, '')
+
+# --------------------------------------------------- class tree extraction
+def walktree(classes, children, parent):
+ """Recursive helper function for getclasstree()."""
+ results = []
+ classes.sort(key=attrgetter('__module__', '__name__'))
+ for c in classes:
+ results.append((c, c.__bases__))
+ if c in children:
+ results.append(walktree(children[c], children, c))
+ return results
+
+def getclasstree(classes, unique=0):
+ """Arrange the given list of classes into a hierarchy of nested lists.
+
+ Where a nested list appears, it contains classes derived from the class
+ whose entry immediately precedes the list. Each entry is a 2-tuple
+ containing a class and a tuple of its base classes. If the 'unique'
+ argument is true, exactly one entry appears in the returned structure
+ for each class in the given list. Otherwise, classes using multiple
+ inheritance and their descendants will appear multiple times."""
+ children = {}
+ roots = []
+ for c in classes:
+ if c.__bases__:
+ for parent in c.__bases__:
+ if not parent in children:
+ children[parent] = []
+ children[parent].append(c)
+ if unique and parent in classes: break
+ elif c not in roots:
+ roots.append(c)
+ for parent in children:
+ if parent not in classes:
+ roots.append(parent)
+ return walktree(roots, children, None)
+
+# ------------------------------------------------ argument list extraction
+Arguments = namedtuple('Arguments', 'args varargs keywords')
+
+def getargs(co):
+ """Get information about the arguments accepted by a code object.
+
+ Three things are returned: (args, varargs, varkw), where 'args' is
+ a list of argument names (possibly containing nested lists), and
+ 'varargs' and 'varkw' are the names of the * and ** arguments or None."""
+
+ if not iscode(co):
+ raise TypeError('arg is not a code object')
+
+ nargs = co.co_argcount
+ names = co.co_varnames
+ args = list(names[:nargs])
+ step = 0
+
+ # The following acrobatics are for anonymous (tuple) arguments.
+ for i in range(nargs):
+ if args[i][:1] in ('', '.'):
+ stack, remain, count = [], [], []
+ while step < len(co.co_code):
+ op = ord(co.co_code[step])
+ step = step + 1
+ if op >= dis.HAVE_ARGUMENT:
+ opname = dis.opname[op]
+ value = ord(co.co_code[step]) + ord(co.co_code[step+1])*256
+ step = step + 2
+ if opname in ('UNPACK_TUPLE', 'UNPACK_SEQUENCE'):
+ remain.append(value)
+ count.append(value)
+ elif opname == 'STORE_FAST':
+ stack.append(names[value])
+
+ # Special case for sublists of length 1: def foo((bar))
+ # doesn't generate the UNPACK_TUPLE bytecode, so if
+ # `remain` is empty here, we have such a sublist.
+ if not remain:
+ stack[0] = [stack[0]]
+ break
+ else:
+ remain[-1] = remain[-1] - 1
+ while remain[-1] == 0:
+ remain.pop()
+ size = count.pop()
+ stack[-size:] = [stack[-size:]]
+ if not remain: break
+ remain[-1] = remain[-1] - 1
+ if not remain: break
+ args[i] = stack[0]
+
+ varargs = None
+ if co.co_flags & CO_VARARGS:
+ varargs = co.co_varnames[nargs]
+ nargs = nargs + 1
+ varkw = None
+ if co.co_flags & CO_VARKEYWORDS:
+ varkw = co.co_varnames[nargs]
+ return Arguments(args, varargs, varkw)
+
+ArgSpec = namedtuple('ArgSpec', 'args varargs keywords defaults')
+
+def getargspec(func):
+ """Get the names and default values of a function's arguments.
+
+ A tuple of four things is returned: (args, varargs, varkw, defaults).
+ 'args' is a list of the argument names (it may contain nested lists).
+ 'varargs' and 'varkw' are the names of the * and ** arguments or None.
+ 'defaults' is an n-tuple of the default values of the last n arguments.
+ """
+
+ if ismethod(func):
+ func = func.im_func
+ if not isfunction(func):
+ raise TypeError('arg is not a Python function')
+ args, varargs, varkw = getargs(func.func_code)
+ return ArgSpec(args, varargs, varkw, func.func_defaults)
+
+ArgInfo = namedtuple('ArgInfo', 'args varargs keywords locals')
+
+def getargvalues(frame):
+ """Get information about arguments passed into a particular frame.
+
+ A tuple of four things is returned: (args, varargs, varkw, locals).
+ 'args' is a list of the argument names (it may contain nested lists).
+ 'varargs' and 'varkw' are the names of the * and ** arguments or None.
+ 'locals' is the locals dictionary of the given frame."""
+ args, varargs, varkw = getargs(frame.f_code)
+ return ArgInfo(args, varargs, varkw, frame.f_locals)
+
+def joinseq(seq):
+ if len(seq) == 1:
+ return '(' + seq[0] + ',)'
+ else:
+ return '(' + string.join(seq, ', ') + ')'
+
+def strseq(object, convert, join=joinseq):
+ """Recursively walk a sequence, stringifying each element."""
+ if type(object) in (list, tuple):
+ return join(map(lambda o, c=convert, j=join: strseq(o, c, j), object))
+ else:
+ return convert(object)
+
+def formatargspec(args, varargs=None, varkw=None, defaults=None,
+ formatarg=str,
+ formatvarargs=lambda name: '*' + name,
+ formatvarkw=lambda name: '**' + name,
+ formatvalue=lambda value: '=' + repr(value),
+ join=joinseq):
+ """Format an argument spec from the 4 values returned by getargspec.
+
+ The first four arguments are (args, varargs, varkw, defaults). The
+ other four arguments are the corresponding optional formatting functions
+ that are called to turn names and values into strings. The ninth
+ argument is an optional function to format the sequence of arguments."""
+ specs = []
+ if defaults:
+ firstdefault = len(args) - len(defaults)
+ for i in range(len(args)):
+ spec = strseq(args[i], formatarg, join)
+ if defaults and i >= firstdefault:
+ spec = spec + formatvalue(defaults[i - firstdefault])
+ specs.append(spec)
+ if varargs is not None:
+ specs.append(formatvarargs(varargs))
+ if varkw is not None:
+ specs.append(formatvarkw(varkw))
+ return '(' + string.join(specs, ', ') + ')'
+
+def formatargvalues(args, varargs, varkw, locals,
+ formatarg=str,
+ formatvarargs=lambda name: '*' + name,
+ formatvarkw=lambda name: '**' + name,
+ formatvalue=lambda value: '=' + repr(value),
+ join=joinseq):
+ """Format an argument spec from the 4 values returned by getargvalues.
+
+ The first four arguments are (args, varargs, varkw, locals). The
+ next four arguments are the corresponding optional formatting functions
+ that are called to turn names and values into strings. The ninth
+ argument is an optional function to format the sequence of arguments."""
+ def convert(name, locals=locals,
+ formatarg=formatarg, formatvalue=formatvalue):
+ return formatarg(name) + formatvalue(locals[name])
+ specs = []
+ for i in range(len(args)):
+ specs.append(strseq(args[i], convert, join))
+ if varargs:
+ specs.append(formatvarargs(varargs) + formatvalue(locals[varargs]))
+ if varkw:
+ specs.append(formatvarkw(varkw) + formatvalue(locals[varkw]))
+ return '(' + string.join(specs, ', ') + ')'
+
+# -------------------------------------------------- stack frame extraction
+
+Traceback = namedtuple('Traceback', 'filename lineno function code_context index')
+
+def getframeinfo(frame, context=1):
+ """Get information about a frame or traceback object.
+
+ A tuple of five things is returned: the filename, the line number of
+ the current line, the function name, a list of lines of context from
+ the source code, and the index of the current line within that list.
+ The optional second argument specifies the number of lines of context
+ to return, which are centered around the current line."""
+ if istraceback(frame):
+ lineno = frame.tb_lineno
+ frame = frame.tb_frame
+ else:
+ lineno = frame.f_lineno
+ if not isframe(frame):
+ raise TypeError('arg is not a frame or traceback object')
+
+ filename = getsourcefile(frame) or getfile(frame)
+ if context > 0:
+ start = lineno - 1 - context//2
+ try:
+ lines, lnum = findsource(frame)
+ except IOError:
+ lines = index = None
+ else:
+ start = max(start, 1)
+ start = max(0, min(start, len(lines) - context))
+ lines = lines[start:start+context]
+ index = lineno - 1 - start
+ else:
+ lines = index = None
+
+ return Traceback(filename, lineno, frame.f_code.co_name, lines, index)
+
+def getlineno(frame):
+ """Get the line number from a frame object, allowing for optimization."""
+ # FrameType.f_lineno is now a descriptor that grovels co_lnotab
+ return frame.f_lineno
+
+def getouterframes(frame, context=1):
+ """Get a list of records for a frame and all higher (calling) frames.
+
+ Each record contains a frame object, filename, line number, function
+ name, a list of lines of context, and index within the context."""
+ framelist = []
+ while frame:
+ framelist.append((frame,) + getframeinfo(frame, context))
+ frame = frame.f_back
+ return framelist
+
+def getinnerframes(tb, context=1):
+ """Get a list of records for a traceback's frame and all lower frames.
+
+ Each record contains a frame object, filename, line number, function
+ name, a list of lines of context, and index within the context."""
+ framelist = []
+ while tb:
+ framelist.append((tb.tb_frame,) + getframeinfo(tb, context))
+ tb = tb.tb_next
+ return framelist
+
+currentframe = sys._getframe
+
+def stack(context=1):
+ """Return a list of records for the stack above the caller's frame."""
+ return getouterframes(sys._getframe(1), context)
+
+def trace(context=1):
+ """Return a list of records for the stack below the current exception."""
+ return getinnerframes(sys.exc_info()[2], context)