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» </li> <li>PEP 367</li> </ul> <button id="colour-scheme-cycler" onClick="setColourScheme(nextColourScheme())"> <svg aria-hidden="true" class="colour-scheme-icon-when-auto"><use href="#svg-sun-half"></use></svg> <svg aria-hidden="true" class="colour-scheme-icon-when-dark"><use href="#svg-moon"></use></svg> <svg aria-hidden="true" class="colour-scheme-icon-when-light"><use href="#svg-sun"></use></svg> Toggle light / dark / auto colour theme </button> </header> <article> <section id="pep-content"> <h1 class="page-title">PEP 367 – New Super</h1> <dl class="rfc2822 field-list simple"> <dt class="field-odd">Author:</dt> <dd class="field-odd">Calvin Spealman <ironfroggy at gmail.com>, Tim Delaney <timothy.c.delaney at gmail.com></dd> <dt class="field-even">Status:</dt> <dd class="field-even"><abbr title="Replaced by another succeeding PEP">Superseded</abbr></dd> <dt class="field-odd">Type:</dt> <dd class="field-odd"><abbr title="Normative PEP with a new feature for Python, implementation change for CPython or interoperability standard for the ecosystem">Standards Track</abbr></dd> <dt class="field-even">Created:</dt> <dd class="field-even">28-Apr-2007</dd> <dt class="field-odd">Python-Version:</dt> <dd class="field-odd">2.6</dd> <dt class="field-even">Post-History:</dt> <dd class="field-even"><a class="reference external" href="https://mail.python.org/pipermail/python-dev/2007-April/072807.html" title="Python-Dev message">28-Apr-2007</a>, <a class="reference external" href="https://mail.python.org/pipermail/python-dev/2007-April/072835.html" title="Python-Dev message">29-Apr-2007</a>, <a class="reference external" href="https://mail.python.org/pipermail/python-dev/2007-April/072858.html" title="Python-Dev message">29-Apr-2007</a>, <a class="reference external" href="https://mail.python.org/pipermail/python-dev/2007-May/073127.html" title="Python-Dev message">14-May-2007</a></dd> </dl> <hr class="docutils" /> <section id="contents"> <details><summary>Table of Contents</summary><ul class="simple"> <li><a class="reference internal" href="#numbering-note">Numbering Note</a></li> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a><ul> <li><a class="reference internal" href="#open-issues">Open Issues</a><ul> <li><a class="reference internal" href="#determining-the-class-object-to-use">Determining the class object to use</a></li> <li><a class="reference internal" href="#should-super-actually-become-a-keyword">Should <code class="docutils literal notranslate">super</code> actually become a keyword?</a></li> </ul> </li> <li><a class="reference internal" href="#closed-issues">Closed Issues</a><ul> <li><a class="reference internal" href="#super-used-with-call-attributes">super used with __call__ attributes</a></li> </ul> </li> </ul> </li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a></li> <li><a class="reference internal" href="#alternative-proposals">Alternative Proposals</a><ul> <li><a class="reference internal" href="#no-changes">No Changes</a></li> <li><a class="reference internal" href="#dynamic-attribute-on-super-type">Dynamic attribute on super type</a></li> <li><a class="reference internal" href="#super-this-class-self">super(__this_class__, self)</a></li> <li><a class="reference internal" href="#self-super-foo-args">self.__super__.foo(*args)</a></li> <li><a class="reference internal" href="#super-self-args-or-super-self-args">super(self, *args) or __super__(self, *args)</a></li> <li><a class="reference internal" href="#super-foo-self-args">super.foo(self, *args)</a></li> <li><a class="reference internal" href="#super-or-super">super or super()</a></li> <li><a class="reference internal" href="#super-p-kw">super(*p, **kw)</a></li> </ul> </li> <li><a class="reference internal" href="#history">History</a></li> <li><a class="reference internal" href="#references">References</a></li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> </details></section> <section id="numbering-note"> <h2><a class="toc-backref" href="#numbering-note" role="doc-backlink">Numbering Note</a></h2> This PEP has been renumbered to <a class="pep reference internal" href="../pep-3135/" title="PEP 3135 – New Super">PEP 3135</a>. The text below is the last version submitted under the old number. </section> <section id="abstract"> <h2><a class="toc-backref" href="#abstract" role="doc-backlink">Abstract</a></h2> This PEP proposes syntactic sugar for use of the <code class="docutils literal notranslate">super</code> type to automatically construct instances of the super type binding to the class that a method was defined in, and the instance (or class object for classmethods) that the method is currently acting upon. The premise of the new super usage suggested is as follows: <div class="highlight-default notranslate"><div class="highlight"><pre>super.foo(1, 2) </pre></div> </div> to replace the old: <div class="highlight-default notranslate"><div class="highlight"><pre>super(Foo, self).foo(1, 2) </pre></div> </div> and the current <code class="docutils literal notranslate">__builtin__.super</code> be aliased to <code class="docutils literal notranslate">__builtin__.__super__</code> (with <code class="docutils literal notranslate">__builtin__.super</code> to be removed in Python 3.0). It is further proposed that assignment to <code class="docutils literal notranslate">super</code> become a <code class="docutils literal notranslate">SyntaxError</code>, similar to the behaviour of <code class="docutils literal notranslate">None</code>. </section> <section id="rationale"> <h2><a class="toc-backref" href="#rationale" role="doc-backlink">Rationale</a></h2> The current usage of super requires an explicit passing of both the class and instance it must operate from, requiring a breaking of the DRY (Don’t Repeat Yourself) rule. This hinders any change in class name, and is often considered a wart by many. </section> <section id="specification"> <h2><a class="toc-backref" href="#specification" role="doc-backlink">Specification</a></h2> Within the specification section, some special terminology will be used to distinguish similar and closely related concepts. “super type” will refer to the actual builtin type named “super”. A “super instance” is simply an instance of the super type, which is associated with a class and possibly with an instance of that class. Because the new <code class="docutils literal notranslate">super</code> semantics are not backwards compatible with Python 2.5, the new semantics will require a <code class="docutils literal notranslate">__future__</code> import: <div class="highlight-default notranslate"><div class="highlight"><pre>from __future__ import new_super </pre></div> </div> The current <code class="docutils literal notranslate">__builtin__.super</code> will be aliased to <code class="docutils literal notranslate">__builtin__.__super__</code>. This will occur regardless of whether the new <code class="docutils literal notranslate">super</code> semantics are active. It is not possible to simply rename <code class="docutils literal notranslate">__builtin__.super</code>, as that would affect modules that do not use the new <code class="docutils literal notranslate">super</code> semantics. In Python 3.0 it is proposed that the name <code class="docutils literal notranslate">__builtin__.super</code> will be removed. Replacing the old usage of super, calls to the next class in the MRO (method resolution order) can be made without explicitly creating a <code class="docutils literal notranslate">super</code> instance (although doing so will still be supported via <code class="docutils literal notranslate">__super__</code>). Every function will have an implicit local named <code class="docutils literal notranslate">super</code>. This name behaves identically to a normal local, including use by inner functions via a cell, with the following exceptions: <ol class="arabic simple"> <li>Assigning to the name <code class="docutils literal notranslate">super</code> will raise a <code class="docutils literal notranslate">SyntaxError</code> at compile time;</li> <li>Calling a static method or normal function that accesses the name <code class="docutils literal notranslate">super</code> will raise a <code class="docutils literal notranslate">TypeError</code> at runtime.</li> </ol> Every function that uses the name <code class="docutils literal notranslate">super</code>, or has an inner function that uses the name <code class="docutils literal notranslate">super</code>, will include a preamble that performs the equivalent of: <div class="highlight-default notranslate"><div class="highlight"><pre>super = __builtin__.__super__(<class>, <instance>) </pre></div> </div> where <code class="docutils literal notranslate"><class></code> is the class that the method was defined in, and <code class="docutils literal notranslate"><instance></code> is the first parameter of the method (normally <code class="docutils literal notranslate">self</code> for instance methods, and <code class="docutils literal notranslate">cls</code> for class methods). For static methods and normal functions, <code class="docutils literal notranslate"><class></code> will be <code class="docutils literal notranslate">None</code>, resulting in a <code class="docutils literal notranslate">TypeError</code> being raised during the preamble. Note: The relationship between <code class="docutils literal notranslate">super</code> and <code class="docutils literal notranslate">__super__</code> is similar to that between <code class="docutils literal notranslate">import</code> and <code class="docutils literal notranslate">__import__</code>. Much of this was discussed in the thread of the python-dev list, “Fixing super anyone?” <a class="footnote-reference brackets" href="#id3" id="id1">[1]</a>. <section id="open-issues"> <h3><a class="toc-backref" href="#open-issues" role="doc-backlink">Open Issues</a></h3> <section id="determining-the-class-object-to-use"> <h4><a class="toc-backref" href="#determining-the-class-object-to-use" role="doc-backlink">Determining the class object to use</a></h4> The exact mechanism for associating the method with the defining class is not specified in this PEP, and should be chosen for maximum performance. For CPython, it is suggested that the class instance be held in a C-level variable on the function object which is bound to one of <code class="docutils literal notranslate">NULL</code> (not part of a class), <code class="docutils literal notranslate">Py_None</code> (static method) or a class object (instance or class method). </section> <section id="should-super-actually-become-a-keyword"> <h4><a class="toc-backref" href="#should-super-actually-become-a-keyword" role="doc-backlink">Should <code class="docutils literal notranslate">super</code> actually become a keyword?</a></h4> With this proposal, <code class="docutils literal notranslate">super</code> would become a keyword to the same extent that <code class="docutils literal notranslate">None</code> is a keyword. It is possible that further restricting the <code class="docutils literal notranslate">super</code> name may simplify implementation, however some are against the actual keyword-ization of super. The simplest solution is often the correct solution and the simplest solution may well not be adding additional keywords to the language when they are not needed. Still, it may solve other open issues. </section> </section> <section id="closed-issues"> <h3><a class="toc-backref" href="#closed-issues" role="doc-backlink">Closed Issues</a></h3> <section id="super-used-with-call-attributes"> <h4><a class="toc-backref" href="#super-used-with-call-attributes" role="doc-backlink">super used with __call__ attributes</a></h4> It was considered that it might be a problem that instantiating super instances the classic way, because calling it would lookup the __call__ attribute and thus try to perform an automatic super lookup to the next class in the MRO. However, this was found to be false, because calling an object only looks up the __call__ method directly on the object’s type. The following example shows this in action. <div class="highlight-default notranslate"><div class="highlight"><pre>class A(object): def __call__(self): return '__call__' def __getattribute__(self, attr): if attr == '__call__': return lambda: '__getattribute__' a = A() assert a() == '__call__' assert a.__call__() == '__getattribute__' </pre></div> </div> In any case, with the renaming of <code class="docutils literal notranslate">__builtin__.super</code> to <code class="docutils literal notranslate">__builtin__.__super__</code> this issue goes away entirely. </section> </section> </section> <section id="reference-implementation"> <h2><a class="toc-backref" href="#reference-implementation" role="doc-backlink">Reference Implementation</a></h2> It is impossible to implement the above specification entirely in Python. This reference implementation has the following differences to the specification: <ol class="arabic simple"> <li>New <code class="docutils literal notranslate">super</code> semantics are implemented using bytecode hacking.</li> <li>Assignment to <code class="docutils literal notranslate">super</code> is not a <code class="docutils literal notranslate">SyntaxError</code>. Also see point #4.</li> <li>Classes must either use the metaclass <code class="docutils literal notranslate">autosuper_meta</code> or inherit from the base class <code class="docutils literal notranslate">autosuper</code> to acquire the new <code class="docutils literal notranslate">super</code> semantics.</li> <li><code class="docutils literal notranslate">super</code> is not an implicit local variable. In particular, for inner functions to be able to use the super instance, there must be an assignment of the form <code class="docutils literal notranslate">super = super</code> in the method.</li> </ol> The reference implementation assumes that it is being run on Python 2.5+. <div class="highlight-default notranslate"><div class="highlight"><pre>#!/usr/bin/env python # # autosuper.py from array import array import dis import new import types import __builtin__ __builtin__.__super__ = __builtin__.super del __builtin__.super # We need these for modifying bytecode from opcode import opmap, HAVE_ARGUMENT, EXTENDED_ARG LOAD_GLOBAL = opmap['LOAD_GLOBAL'] LOAD_NAME = opmap['LOAD_NAME'] LOAD_CONST = opmap['LOAD_CONST'] LOAD_FAST = opmap['LOAD_FAST'] LOAD_ATTR = opmap['LOAD_ATTR'] STORE_FAST = opmap['STORE_FAST'] LOAD_DEREF = opmap['LOAD_DEREF'] STORE_DEREF = opmap['STORE_DEREF'] CALL_FUNCTION = opmap['CALL_FUNCTION'] STORE_GLOBAL = opmap['STORE_GLOBAL'] DUP_TOP = opmap['DUP_TOP'] POP_TOP = opmap['POP_TOP'] NOP = opmap['NOP'] JUMP_FORWARD = opmap['JUMP_FORWARD'] ABSOLUTE_TARGET = dis.hasjabs def _oparg(code, opcode_pos): return code[opcode_pos+1] + (code[opcode_pos+2] << 8) def _bind_autosuper(func, cls): co = func.func_code name = func.func_name newcode = array('B', co.co_code) codelen = len(newcode) newconsts = list(co.co_consts) newvarnames = list(co.co_varnames) # Check if the global 'super' keyword is already present try: sn_pos = list(co.co_names).index('super') except ValueError: sn_pos = None # Check if the varname 'super' keyword is already present try: sv_pos = newvarnames.index('super') except ValueError: sv_pos = None # Check if the cellvar 'super' keyword is already present try: sc_pos = list(co.co_cellvars).index('super') except ValueError: sc_pos = None # If 'super' isn't used anywhere in the function, we don't have anything to do if sn_pos is None and sv_pos is None and sc_pos is None: return func c_pos = None s_pos = None n_pos = None # Check if the 'cls_name' and 'super' objects are already in the constants for pos, o in enumerate(newconsts): if o is cls: c_pos = pos if o is __super__: s_pos = pos if o == name: n_pos = pos # Add in any missing objects to constants and varnames if c_pos is None: c_pos = len(newconsts) newconsts.append(cls) if n_pos is None: n_pos = len(newconsts) newconsts.append(name) if s_pos is None: s_pos = len(newconsts) newconsts.append(__super__) if sv_pos is None: sv_pos = len(newvarnames) newvarnames.append('super') # This goes at the start of the function. It is: # # super = __super__(cls, self) # # If 'super' is a cell variable, we store to both the # local and cell variables (i.e. STORE_FAST and STORE_DEREF). # preamble = [ LOAD_CONST, s_pos & 0xFF, s_pos >> 8, LOAD_CONST, c_pos & 0xFF, c_pos >> 8, LOAD_FAST, 0, 0, CALL_FUNCTION, 2, 0, ] if sc_pos is None: # 'super' is not a cell variable - we can just use the local variable preamble += [ STORE_FAST, sv_pos & 0xFF, sv_pos >> 8, ] else: # If 'super' is a cell variable, we need to handle LOAD_DEREF. preamble += [ DUP_TOP, STORE_FAST, sv_pos & 0xFF, sv_pos >> 8, STORE_DEREF, sc_pos & 0xFF, sc_pos >> 8, ] preamble = array('B', preamble) # Bytecode for loading the local 'super' variable. load_super = array('B', [ LOAD_FAST, sv_pos & 0xFF, sv_pos >> 8, ]) preamble_len = len(preamble) need_preamble = False i = 0 while i < codelen: opcode = newcode[i] need_load = False remove_store = False if opcode == EXTENDED_ARG: raise TypeError("Cannot use 'super' in function with EXTENDED_ARG opcode") # If the opcode is an absolute target it needs to be adjusted # to take into account the preamble. elif opcode in ABSOLUTE_TARGET: oparg = _oparg(newcode, i) + preamble_len newcode[i+1] = oparg & 0xFF newcode[i+2] = oparg >> 8 # If LOAD_GLOBAL(super) or LOAD_NAME(super) then we want to change it into # LOAD_FAST(super) elif (opcode == LOAD_GLOBAL or opcode == LOAD_NAME) and _oparg(newcode, i) == sn_pos: need_preamble = need_load = True # If LOAD_FAST(super) then we just need to add the preamble elif opcode == LOAD_FAST and _oparg(newcode, i) == sv_pos: need_preamble = need_load = True # If LOAD_DEREF(super) then we change it into LOAD_FAST(super) because # it's slightly faster. elif opcode == LOAD_DEREF and _oparg(newcode, i) == sc_pos: need_preamble = need_load = True if need_load: newcode[i:i+3] = load_super i += 1 if opcode >= HAVE_ARGUMENT: i += 2 # No changes needed - get out. if not need_preamble: return func # Our preamble will have 3 things on the stack co_stacksize = max(3, co.co_stacksize) # Conceptually, our preamble is on the `def` line. co_lnotab = array('B', co.co_lnotab) if co_lnotab: co_lnotab[0] += preamble_len co_lnotab = co_lnotab.tostring() # Our code consists of the preamble and the modified code. codestr = (preamble + newcode).tostring() codeobj = new.code(co.co_argcount, len(newvarnames), co_stacksize, co.co_flags, codestr, tuple(newconsts), co.co_names, tuple(newvarnames), co.co_filename, co.co_name, co.co_firstlineno, co_lnotab, co.co_freevars, co.co_cellvars) func.func_code = codeobj func.func_class = cls return func class autosuper_meta(type): def __init__(cls, name, bases, clsdict): UnboundMethodType = types.UnboundMethodType for v in vars(cls): o = getattr(cls, v) if isinstance(o, UnboundMethodType): _bind_autosuper(o.im_func, cls) class autosuper(object): __metaclass__ = autosuper_meta if __name__ == '__main__': class A(autosuper): def f(self): return 'A' class B(A): def f(self): return 'B' + super.f() class C(A): def f(self): def inner(): return 'C' + super.f() # Needed to put 'super' into a cell super = super return inner() class D(B, C): def f(self, arg=None): var = None return 'D' + super.f() assert D().f() == 'DBCA' </pre></div> </div> Disassembly of B.f and C.f reveals the different preambles used when <code class="docutils literal notranslate">super</code> is simply a local variable compared to when it is used by an inner function. <div class="highlight-default notranslate"><div class="highlight"><pre>>>> dis.dis(B.f) 214 0 LOAD_CONST 4 (<type 'super'>) 3 LOAD_CONST 2 (<class '__main__.B'>) 6 LOAD_FAST 0 (self) 9 CALL_FUNCTION 2 12 STORE_FAST 1 (super) 215 15 LOAD_CONST 1 ('B') 18 LOAD_FAST 1 (super) 21 LOAD_ATTR 1 (f) 24 CALL_FUNCTION 0 27 BINARY_ADD 28 RETURN_VALUE </pre></div> </div> <div class="highlight-default notranslate"><div class="highlight"><pre>>>> dis.dis(C.f) 218 0 LOAD_CONST 4 (<type 'super'>) 3 LOAD_CONST 2 (<class '__main__.C'>) 6 LOAD_FAST 0 (self) 9 CALL_FUNCTION 2 12 DUP_TOP 13 STORE_FAST 1 (super) 16 STORE_DEREF 0 (super) 219 19 LOAD_CLOSURE 0 (super) 22 LOAD_CONST 1 (<code object inner at 00C160A0, file "autosuper.py", line 219>) 25 MAKE_CLOSURE 0 28 STORE_FAST 2 (inner) 223 31 LOAD_FAST 1 (super) 34 STORE_DEREF 0 (super) 224 37 LOAD_FAST 2 (inner) 40 CALL_FUNCTION 0 43 RETURN_VALUE </pre></div> </div> Note that in the final implementation, the preamble would not be part of the bytecode of the method, but would occur immediately following unpacking of parameters. </section> <section id="alternative-proposals"> <h2><a class="toc-backref" href="#alternative-proposals" role="doc-backlink">Alternative Proposals</a></h2> <section id="no-changes"> <h3><a class="toc-backref" href="#no-changes" role="doc-backlink">No Changes</a></h3> Although its always attractive to just keep things how they are, people have sought a change in the usage of super calling for some time, and for good reason, all mentioned previously. <ul class="simple"> <li>Decoupling from the class name (which might not even be bound to the right class anymore!)</li> <li>Simpler looking, cleaner super calls would be better</li> </ul> </section> <section id="dynamic-attribute-on-super-type"> <h3><a class="toc-backref" href="#dynamic-attribute-on-super-type" role="doc-backlink">Dynamic attribute on super type</a></h3> The proposal adds a dynamic attribute lookup to the super type, which will automatically determine the proper class and instance parameters. Each super attribute lookup identifies these parameters and performs the super lookup on the instance, as the current super implementation does with the explicit invocation of a super instance upon a class and instance. This proposal relies on sys._getframe(), which is not appropriate for anything except a prototype implementation. </section> <section id="super-this-class-self"> <h3><a class="toc-backref" href="#super-this-class-self" role="doc-backlink">super(__this_class__, self)</a></h3> This is nearly an anti-proposal, as it basically relies on the acceptance of the __this_class__ PEP, which proposes a special name that would always be bound to the class within which it is used. If that is accepted, __this_class__ could simply be used instead of the class’ name explicitly, solving the name binding issues <a class="footnote-reference brackets" href="#id4" id="id2">[2]</a>. </section> <section id="self-super-foo-args"> <h3><a class="toc-backref" href="#self-super-foo-args" role="doc-backlink">self.__super__.foo(*args)</a></h3> The __super__ attribute is mentioned in this PEP in several places, and could be a candidate for the complete solution, actually using it explicitly instead of any super usage directly. However, double-underscore names are usually an internal detail, and attempted to be kept out of everyday code. </section> <section id="super-self-args-or-super-self-args"> <h3><a class="toc-backref" href="#super-self-args-or-super-self-args" role="doc-backlink">super(self, *args) or __super__(self, *args)</a></h3> This solution only solves the problem of the type indication, does not handle differently named super methods, and is explicit about the name of the instance. It is less flexible without being able to enacted on other method names, in cases where that is needed. One use case this fails is where a base-class has a factory classmethod and a subclass has two factory classmethods, both of which needing to properly make super calls to the one in the base-class. </section> <section id="super-foo-self-args"> <h3><a class="toc-backref" href="#super-foo-self-args" role="doc-backlink">super.foo(self, *args)</a></h3> This variation actually eliminates the problems with locating the proper instance, and if any of the alternatives were pushed into the spotlight, I would want it to be this one. </section> <section id="super-or-super"> <h3><a class="toc-backref" href="#super-or-super" role="doc-backlink">super or super()</a></h3> This proposal leaves no room for different names, signatures, or application to other classes, or instances. A way to allow some similar use alongside the normal proposal would be favorable, encouraging good design of multiple inheritance trees and compatible methods. </section> <section id="super-p-kw"> <h3><a class="toc-backref" href="#super-p-kw" role="doc-backlink">super(*p, **kw)</a></h3> There has been the proposal that directly calling <code class="docutils literal notranslate">super(*p, **kw)</code> would be equivalent to calling the method on the <code class="docutils literal notranslate">super</code> object with the same name as the method currently being executed i.e. the following two methods would be equivalent: <div class="highlight-default notranslate"><div class="highlight"><pre>def f(self, *p, **kw): super.f(*p, **kw) </pre></div> </div> <div class="highlight-default notranslate"><div class="highlight"><pre>def f(self, *p, **kw): super(*p, **kw) </pre></div> </div> There is strong sentiment for and against this, but implementation and style concerns are obvious. Guido has suggested that this should be excluded from this PEP on the principle of KISS (Keep It Simple Stupid). </section> </section> <section id="history"> <h2><a class="toc-backref" href="#history" role="doc-backlink">History</a></h2> <dl class="simple"> <dt>29-Apr-2007 - Changed title from “Super As A Keyword” to “New Super”</dt><dd><ul class="simple"> <li>Updated much of the language and added a terminology section for clarification in confusing places.</li> <li>Added reference implementation and history sections.</li> </ul> </dd> <dt>06-May-2007 - Updated by Tim Delaney to reflect discussions on the python-3000</dt><dd>and python-dev mailing lists.</dd> </dl> </section> <section id="references"> <h2><a class="toc-backref" href="#references" role="doc-backlink">References</a></h2> <aside class="footnote-list brackets"> <aside class="footnote brackets" id="id3" role="doc-footnote"> <dt class="label" id="id3">[<a href="#id1">1</a>]</dt> <dd>Fixing super anyone? (<a class="reference external" href="https://mail.python.org/pipermail/python-3000/2007-April/006667.html">https://mail.python.org/pipermail/python-3000/2007-April/006667.html</a>)</aside> <aside class="footnote brackets" id="id4" role="doc-footnote"> <dt class="label" id="id4">[<a href="#id2">2</a>]</dt> <dd>PEP 3130: Access to Module/Class/Function Currently Being Defined (this) (<a class="reference external" href="https://mail.python.org/pipermail/python-ideas/2007-April/000542.html">https://mail.python.org/pipermail/python-ideas/2007-April/000542.html</a>)</aside> </aside> </section> <section id="copyright"> <h2><a class="toc-backref" href="#copyright" role="doc-backlink">Copyright</a></h2> This document has been placed in the public domain. </section> </section> <hr class="docutils" /> Source: <a class="reference external" href="https://github.com/python/peps/blob/main/peps/pep-0367.rst">https://github.com/python/peps/blob/main/peps/pep-0367.rst</a> Last modified: <a class="reference external" href="https://github.com/python/peps/commits/main/peps/pep-0367.rst">2025-02-01 08:59:27 GMT</a> </article> <nav id="pep-sidebar"> <h2>Contents</h2> <ul> <li><a class="reference internal" href="#numbering-note">Numbering Note</a></li> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a><ul> <li><a class="reference internal" href="#open-issues">Open Issues</a><ul> <li><a class="reference internal" href="#determining-the-class-object-to-use">Determining the class object to use</a></li> <li><a class="reference internal" href="#should-super-actually-become-a-keyword">Should <code class="docutils literal notranslate">super</code> actually become a keyword?</a></li> </ul> </li> <li><a class="reference internal" href="#closed-issues">Closed Issues</a><ul> <li><a class="reference internal" href="#super-used-with-call-attributes">super used with __call__ attributes</a></li> </ul> </li> </ul> </li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a></li> <li><a class="reference internal" href="#alternative-proposals">Alternative Proposals</a><ul> <li><a class="reference internal" href="#no-changes">No Changes</a></li> <li><a class="reference internal" href="#dynamic-attribute-on-super-type">Dynamic attribute on super type</a></li> <li><a class="reference internal" href="#super-this-class-self">super(__this_class__, self)</a></li> <li><a class="reference internal" href="#self-super-foo-args">self.__super__.foo(*args)</a></li> <li><a class="reference internal" href="#super-self-args-or-super-self-args">super(self, *args) or __super__(self, *args)</a></li> <li><a class="reference internal" href="#super-foo-self-args">super.foo(self, *args)</a></li> <li><a class="reference internal" href="#super-or-super">super or super()</a></li> <li><a class="reference internal" href="#super-p-kw">super(*p, **kw)</a></li> </ul> </li> <li><a class="reference internal" href="#history">History</a></li> <li><a class="reference internal" href="#references">References</a></li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> <a id="source" href="https://github.com/python/peps/blob/main/peps/pep-0367.rst">Page Source (GitHub)</a> </nav> </section> <script src="../_static/colour_scheme.js"></script> <script src="../_static/wrap_tables.js"></script> <script src="../_static/sticky_banner.js"></script> </body> </html>