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...Constant AST node prepopulated with a complex number. If that was the way things worked, then complex literals could be accepted through a similar mechanism to any other literal. This isn't how complex literals are handled, however. Instead, they're passed through to the AST as regular BinOp nodes, and then the constant folding pass on the AST resolves them down to Constant nodes with a complex value. For the parser to resolve complex literals directly, the compiler would need to be able to tell...
...constants or use more than one million names. The number of distinct names in a code object. The number of constants in a code object. The advantages for CPython of imposing these limits: Line of code in a module and code object restrictions. When compiling source code to bytecode or modifying bytecode for profiling or debugging, an intermediate form is required. By limiting operands to 23 bits, instructions can be represented in a compact 64 bit form allowing very fast passes over the inst...
...constants into a single constant. SF bug #513866: Float/long comparison anomaly. Prior to 2.4b1, when an integer was compared to a float, the integer was coerced to a float. That could yield spurious overflow errors (if the integer was very large), and to anomalies such as long(1e200)+1 == 1e200 == long(1e200)-1. Coercion to float is no longer performed, and cases like long(1e200)-1 < 1e200, long(1e200)+1 > 1e200 and (1 << 20000) > 1e200 are computed correctly now. Extension...
...constants (C unsigned ints). Each of these constants does not refer to an entire cipher suite, but instead an individual algorithm. Some examples are CALG_3DES and CALG_AES_256, which refer to the bulk encryption algorithm used in a cipher suite, CALG_DH_EPHEM and CALG_RSA_KEYX which refer to part of the key exchange algorithm used in a cipher suite, CALG_SHA1 and CALG_MD5 which refer to the message authentication code used in a cipher suite, and CALG_ECDSA and CALG_RSA_SIGN which refer to the s...
...constants that describe the columns in the database. This way we can add new tables to the overall API quickly and simply without having to worry about implementation details for any specific table. The API also uses meta-data to automatically validate and convert values passed to the database. This is done by a "normalizer" function that converts the Python data types being passed through the API into valid SQL values. The function also verifies types and formats that are not necessa...
...constants with a leading minus sign would come out with the wrong sign. ("Unsigned" hex/oct constants are those with a face value in the range sys.maxint+1 through sys.maxint*2+1, inclusive; these have always been interpreted as negative numbers through sign folding.) E.g. 0xffffffff is -1, and -(0xffffffff) is 1, but -0xffffffff would come out as -4294967295. This was the case in Python 2.2 through 2.2.2 and 2.3a1, and in Python 2.4 it will once again have that value, but according t...
...constants: Constant Description FIRST_COMPLETED The method will return when any future finishes or is cancelled. FIRST_EXCEPTION The method will return when any future finishes by raising an exception. If not future raises an exception then it is equivalent to ALL_COMPLETED. ALL_COMPLETED The method will return when all calls finish. as_completed(fs, timeout=None) Returns an iterator over the Future instances given by fs that yields futures as they complete (finished or were canc...
...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...
...constants – will be explicitly listed in a single "manifest" file, Misc/stable_abi.txt. For structs, any fields that users of the Stable ABI are allowed to access will be listed explicitly. The manifest will also serve as the definitive list of the Limited API. Members that are not part of the Limited API, but are part of the Stable ABI (e.g. PyObject.ob_type, which is accessible by the Py_TYPE macro), will be annotated as such. For items that are only available on some systems, the manifest wil...
...constant feedback through the audio device about their current location on the map by associating sounds with surface types. Our next concern was whether Python could retrieve the information from the data structure fast enough to provide responsive feedback to our end user. Python was however able to execute these operations smoothly and enabled us to give immediate aural feedback about the surface type. Watching the user's cursor on the screen we saw that upon entering the ocean area, the prog...
...constant which is then added to the object's namespace during object construction time. In order to preserve features like inheritance and hiding of Python's special attributes (ones with leading and trailing double underscores), a special name mangling has to be applied which uniquely identifies the docstring as belonging to the name assignment and allows finding the docstring later on by inspecting the namespace. The following name mangling scheme achieves all of the above: __doc_<attribut...
...constant strings. Update the implementations of os.fsencode() and os.fsdecode() to use sys.getfilesystemencodeerrors() instead of assuming the mode. Update path_converter Update the path converter to always decode bytes or buffer objects into text using PyUnicode_DecodeFSDefaultAndSize(). Change the narrow field from a char* string into a flag that indicates whether the original object was bytes. This is required for functions that need to return paths using the same type as was originally pro...
...constants in this file are now in the 'termios' module. Date: 10-Aug-2004 Documentation: This module has been documented as obsolete since Python 2.1, but listing in this PEP was neglected. Removed from the library reference in Python 2.4. Module name: statcache Rationale: Using the cache can be fragile and error-prone; applications should just use os.stat() directly. Date: 10-Aug-2004 Documentation: This module has been docum...
...constant; and use of star-args implies that more than one argument could be given. Specification Function default arguments can be defined using the new => notation: def bisect_right(a, x, lo=0, hi=>len(a), *, key=None): def connect(timeout=>default_timeout): def add_item(item, target=>[]): def format_time(fmt, time_t=>time.time()): The expression is saved in its source code form for the purpose of inspection, and bytecode to evaluate it is prepended to the function's body. No...
...constants, functions, etc.) as the time module. It can be painful to maintain two flavors of the time module. How are users use supposed to make a choice between these two modules? If tomorrow, other nanosecond variants are needed in the os module, will we have to add a new os_ns module as well? There are functions related to time in many modules: time, os, signal, resource, select, etc. Another idea is to add a time.ns submodule or a nested-namespace to get the time.ns.time() syntax, but it suf...
...constant. A warning will be issued if a global statement for a variable follows a use or assignment of that variable. Standard library unittest.py, a unit testing framework by Steve Purcell (PyUNIT, inspired by JUnit), is now part of the standard library. You now have a choice of two testing frameworks: unittest requires you to write testcases as separate code, doctest gathers them from docstrings. Both approaches have their advantages and disadvantages. A new module Tix was added, which wra...
...constant values that have a defined sequence but no inherent semantic meaning. Classic examples are days of the week (Sunday through Saturday) and school assessment grades ('A' through 'D', and 'F'). Other examples include error status values and states within a defined process. It is possible to simply define a sequence of values of some other basic type, such as int or str, to represent discrete arbitrary values. However, an enumeration ensures that such values are distinct from any others,...
...constantly, make sure to delete your old .py(c|o) files! Even though you will end up changing the magic number if you change the bytecode, while you are debugging your work you will be changing the bytecode output without constantly bumping up the magic number. This means you end up with stale .pyc files that will not be recreated. Running find . -name '*.py[co]' -exec rm -f {} ';' should delete all .pyc files you have, forcing new ones to be created and thus allow you test out your new bytec...
...constant-time.diff [7]http://bugs.python.org/file46379/pythread-tss-3.patch [8](1, 2, 3) https://bugs.python.org/msg298342 [9](1, 2) http://bugs.python.org/issue30832 [10]https://github.com/python/cpython/compare/master...ma8ma:pep539-tss-api [11]https://github.com/python/cpython/pull/1362 [12]https://docs.python.org/3/c-api/init.html#c.Py_FinalizeEx [13]It is also called as "stable ABI" (PEP 384) [14]http://pubs.opengroup.org/onlinepubs/009695399/function...