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diff --git a/Misc/NEWS b/Misc/NEWS new file mode 100644 index 0000000..d5f4973 --- /dev/null +++ b/Misc/NEWS @@ -0,0 +1,382 @@ +======================================= +==> Release 1.0.0 (26 January 1994) <== +======================================= + +As is traditional, so many things have changed that I can't pretend to +be complete in these release notes, but I'll try anyway :-) + +Note that the very last section is labeled "remaining bugs". + + +Source organization and build process +------------------------------------- + +* The sources have finally been split: instead of a single src +subdirectory there are now separate directories Include, Parser, +Grammar, Objects, Python and Modules. Other directories also start +with a capital letter: Misc, Doc, Lib, Demo. + +* A few extensions (notably Amoeba and X support) have been moved to a +separate subtree Extensions, which is no longer in the core +distribution, but separately ftp'able as extensions.tar.Z. (The +distribution contains a placeholder Ext-dummy with a description of +the Extensions subtree as well as the most recent versions of the +scripts used there.) + +* A few large specialized demos (SGI video and www) have been +moved to a separate subdirectory Demo2, which is no longer in the core +distribution, but separately ftp'able as demo2.tar.Z. + +* Parts of the standard library have been moved to subdirectories: +there are now standard subdirectories stdwin, test, sgi and sun4. + +* The configuration process has radically changed: I now use GNU +autoconf. This makes it much easier to build on new Unix flavors, as +well as fully supporting VPATH (if your Make has it). The scripts +Configure.py and Addmodule.sh are no longer needed. Many source files +have been adapted in order to work with the symbols that the configure +script generated by autoconf defines (or not); the resulting source is +much more portable to different C compilers and operating systems, +even non Unix systems (a Mac port was done in an afternoon). See the +toplevel README file for a description of the new build process. + +* GNU readline (a slightly newer version) is now a subdirectory of the +Python toplevel. It is still not automatically configured (being +totally autoconf-unaware :-). One problem has been solved: typing +Control-C to a readline prompt will now work. The distribution no +longer contains a "super-level" directory (above the python toplevel +directory), and dl, dl-dld and GNU dld are no longer part of the +Python distribution (you can still ftp them from +ftp.cwi.nl:/pub/dynload). + +* The DOS functions have been taken out of posixmodule.c and moved +into a separate file dosmodule.c. + +* There's now a separate file version.c which contains nothing but +the version number. + +* The actual main program is now contained in config.c (unless NO_MAIN +is defined); pythonmain.c now contains a function realmain() which is +called from config.c's main(). + +* All files needed to use the built-in module md5 are now contained in +the distribution. The module has been cleaned up considerably. + + +Documentation +------------- + +* The library manual has been split into many more small latex files, +so it is easier to edit Doc/lib.tex file to create a custom library +manual, describing only those modules supported on your system. (This +is not automated though.) + +* A fourth manual has been added, titled "Extending and Embedding the +Python Interpreter" (Doc/ext.tex), which collects information about +the interpreter which was previously spread over several files in the +misc subdirectory. + +* The entire documentation is now also available on-line for those who +have a WWW browser (e.g. NCSA Mosaic). Point your browser to the URL +"http://www.cwi.nl/~guido/Python.html". + + +Syntax +------ + +* Strings may now be enclosed in double quotes as well as in single +quotes. There is no difference in interpretation. The repr() of +string objects will use double quotes if the string contains a single +quote and no double quotes. Thanks to Amrit for these changes! + +* There is a new keyword 'exec'. This replaces the exec() built-in +function. If a function contains an exec statement, local variable +optimization is not performed for that particular function, thus +making assignment to local variables in exec statements less +confusing. (As a consequence, os.exec and python.exec have been +renamed to execv.) + +* There is a new keyword 'lambda'. An expression of the form + + lambda <parameters> : <expression> + +yields an anonymous function. This is really only syntactic sugar; +you can just as well define a local function using + + def some_temporary_name(<parameters>): return <expression> + +Lambda expressions are particularly useful in combination with map(), +filter() and reduce(), described below. Thanks to Amrit for +submitting this code (as well as map(), filter(), reduce() and +xrange())! + + +Built-in functions +------------------ + +* The built-in module containing the built-in functions is called +__builtin__ instead of builtin. + +* New built-in functions map(), filter() and reduce() perform standard +functional programming operations (though not lazily): + +- map(f, seq) returns a new sequence whose items are the items from +seq with f() applied to them. + +- filter(f, seq) returns a subsequence of seq consisting of those +items for which f() is true. + +- reduce(f, seq, initial) returns a value computed as follows: + acc = initial + for item in seq: acc = f(acc, item) + return acc + +* New function xrange() creates a "range object". Its arguments are +the same as those of range(), and when used in a for loop a range +objects also behaves identical. The advantage of xrange() over +range() is that its representation (if the range contains many +elements) is much more compact than that of range(). The disadvantage +is that the result cannot be used to initialize a list object or for +the "Python idiom" [RED, GREEN, BLUE] = range(3). On some modern +architectures, benchmarks have shown that "for i in range(...): ..." +actually executes *faster* than "for i in xrange(...): ...", but on +memory starved machines like PCs running DOS range(100000) may be just +too big to be represented at all... + +* Built-in function exec() has been replaced by the exec statement -- +see above. + + +The interpreter +--------------- + +* Syntax errors are now not printed to stderr by the parser, but +rather the offending line and other relevant information are packed up +in the SyntaxError exception argument. When the main loop catches a +SyntaxError exception it will print the error in the same format as +previously, but at the proper position in the stack traceback. + +* You can now set a maximum to the number of traceback entries +printed by assigning to sys.tracebacklimit. The default is 1000. + +* The version number in .pyc files has changed yet again. + +* It is now possible to have a .pyc file without a corresponding .py +file. (Warning: this may break existing installations if you have an +old .pyc file lingering around somewhere on your module search path +without a corresponding .py file, when there is a .py file for a +module of the same name further down the path -- the new interpreter +will find the first .pyc file and complain about it, while the old +interpreter would ignore it and use the .py file further down.) + +* The list sys.builtin_module_names is now sorted and also contains +the names of a few hardwired built-in modules (sys, __main__ and +__builtin__). + +* A module can now find its own name by accessing the global variable +__name__. Assigning to this variable essentially renames the module +(it should also be stored under a different key in sys.modules). +A neat hack follows from this: a module that wants to execute a main +program when called as a script no longer needs to compare +sys.argv[0]; it can simply do "if __name__ == '__main__': main()". + +* When an object is printed by the print statement, its implementation +of str() is used. This means that classes can define __str__(self) to +direct how their instances are printed. This is different from +__repr__(self), which should define an unambigous string +representation of the instance. (If __str__() is not defined, it +defaults to __repr__().) + +* Functions and code objects can now be compared meaningfully. + +* On systems supporting SunOS or SVR4 style shared libraries, dynamic +loading of modules using shared libraries is automatically configured. +Thanks to Bill Jansen and Denis Severson for contributing this change! + + +Built-in objects +---------------- + +* File objects have acquired a new method writelines() which is the +reverse of readlines(). (It does not actually write lines, just a +list of strings, but the symmetry makes the choice of name OK.) + + +Built-in modules +---------------- + +* Socket objects no longer support the avail() method. Use the select +module instead, or use this function to replace it: + + def avail(f): + import select + return f in select.select([f], [], [], 0)[0] + +* Initialization of stdwin is done differently. It actually modifies +sys.argv (taking out the options the X version of stdwin recognizes) +the first time it is imported. + +* A new built-in module parser provides a rudimentary interface to the +python parser. Corresponding standard library modules token and symbol +defines the numeric values of tokens and non-terminal symbols. + +* The posix module has aquired new functions setuid(), setgid(), +execve(), and exec() has been renamed to execv(). + +* The array module is extended with 8-byte object swaps, the 'i' +format character, and a reverse() method. The read() and write() +methods are renamed to fromfile() and tofile(). + +* The rotor module has freed of portability bugs. This introduces a +backward compatibility problem: strings encoded with the old rotor +module can't be decoded by the new version. + +* For select.select(), a timeout (4th) argument of None means the same +as leaving the timeout argument out. + +* Module strop (and hence standard library module string) has aquired +a new function: rindex(). Thanks to Amrit! + +* Module regex defines a new function symcomp() which uses an extended +regular expression syntax: parenthesized subexpressions may be labeled +using the form "\(<labelname>...\)", and the group() method can return +sub-expressions by name. Thanks to Tracy Tims for these changes! + +* Multiple threads are now supported on Solaris 2. Thanks to Sjoerd +Mullender! + + +Standard library modules +------------------------ + +* The library is now split in several subdirectories: all stuff using +stdwin is in Lib/stdwin, all SGI specific (or SGI Indigo or GL) stuff +is in Lib/sgi, all Sun Sparc specific stuff is in Lib/sun4, and all +test modules are in Lib/test. The default module search path will +include all relevant subdirectories by default. + +* Module os now knows about trying to import dos. It defines +functions execl(), execle(), execlp() and execvp(). + +* New module dospath (should be attacked by a DOS hacker though). + +* All modules defining classes now define __init__() constructors +instead of init() methods. THIS IS AN INCOMPATIBLE CHANGE! + +* Some minor changes and bugfixes module ftplib (mostly Steve +Majewski's suggestions); the debug() method is renamed to +set_debuglevel(). + +* Some new test modules (not run automatically by testall though): +test_audioop, test_md5, test_rgbimg, test_select. + +* Module string now defines rindex() and rfind() in analogy of index() +and find(). It also defines atof() and atol() (and corresponding +exceptions) in analogy to atoi(). + +* Added help() functions to modules profile and pdb. + +* The wdb debugger (now in Lib/stdwin) now shows class or instance +variables on a double click. Thanks to Sjoerd Mullender! + +* The (undocumented) module lambda has gone -- you couldn't import it +any more, and it was basically more a demo than a library module... + + +Multimedia extensions +--------------------- + +* The optional built-in modules audioop and imageop are now standard +parts of the interpreter. Thanks to Sjoerd Mullender and Jack Jansen +for contributing this code! + +* There's a new operation in audioop: minmax(). + +* There's a new built-in module called rgbimg which supports portable +efficient reading of SGI RCG image files. Thanks also to Paul +Haeberli for the original code! (Who will contribute a GIF reader?) + +* The module aifc is gone -- you should now always use aifc, which has +received a facelift. + +* There's a new module sunau., for reading Sun (and NeXT) audio files. + +* There's a new module audiodev which provides a uniform interface to +(SGI Indigo and Sun Sparc) audio hardware. + +* There's a new module sndhdr which recognizes various sound files by +looking in their header and checking for various magic words. + + +Optimizations +------------- + +* Most optimizations below can be configured by compile-time flags. +Thanks to Sjoerd Mullender for submitting these optimizations! + +* Small integers (default -1..99) are shared -- i.e. if two different +functions compute the same value it is possible (but not +guaranteed!!!) that they return the same *object*. Python programs +can detect this but should *never* rely on it. + +* Empty tuples (which all compare equal) are shared in the same +manner. + +* Tuples of size up to 20 (default) are put in separate free lists +when deallocated. + +* There is a compile-time option to cache a string's hash function, +but this appeared to have a negligeable effect, and as it costs 4 +bytes per string it is disabled by default. + + +Embedding Python +---------------- + +* The initialization interface has been simplified somewhat. You now +only call "initall()" to initialize the interpreter. + +* The previously announced renaming of externally visible identifiers +has not been carried out. It will happen in a later release. Sorry. + + +Miscellaneous bugs that have been fixed +--------------------------------------- + +* All known portability bugs. + +* Version 0.9.9 dumped core in <listobject>.sort() which has been +fixed. Thanks to Jaap Vermeulen for fixing this and posting the fix +on the mailing list while I was away! + +* Core dump on a format string ending in '%', e.g. in the expression +'%' % None. + +* The array module yielded a bogus result for concatenation (a+b would +yield a+a). + +* Some serious memory leaks in strop.split() and strop.splitfields(). + +* Several problems with the nis module. + +* Subtle problem when copying a class method from another class +through assignment (the method could not be called). + + +Remaining bugs +-------------- + +* One problem with 64-bit machines remains -- since .pyc files are +portable and use only 4 bytes to represent an integer object, 64-bit +integer literals are silently truncated when written into a .pyc file. +Work-around: use eval('123456789101112'). + +* The freeze script doesn't work any more. A new and more portable +one can probably be cooked up using tricks from Extensions/mkext.py. + +* The dos support hasn't been tested yet. (Really Soon Now we should +have a PC with a working C compiler!) + + +--Guido van Rossum, CWI, Amsterdam <Guido.van.Rossum@cwi.nl> +URL: <http://www.cwi.nl/cwi/people/Guido.van.Rossum.html> |