Now that 2.4 is out and everything maybe it's about time to start discussing the "use the __source__ Luke" feature which IMO will really boost python into a new domain of exciting possibilities.
I'm opposed to this idea. It creates overhead in the size of .pyc files, for no additional value that couldn't be obtained otherwise.
As the rationale, the PEP lists:
1.
It is generally a tempting idea to use python as an interface to
a program.
I cannot see how this rationale is related to the PEP. You can use Python as interface to a program with or without __source__.
2.
The developers can implement all the functionality
and instead of designing a user interface, provide a python
interpreter to their users.
This does not require __source, either.
3.
A much more powerful approach would be an interface which is
dynamically constructed by the user to meet the user's needs.
Dynamic code generation doesn't require __source__, either.
4.
The most common development cycle of python programs is:
write .py file - execute .py file - exit - enhance .py file -
execute .py file - etc. With the implementation of the __source__
attribute though the development/modification of python code
can happen at run-time.
This works just fine as well at the moment; see IDLE for an example.
Functions and classes can be defined,
modified or enhanced while the python shell is running and
all the changes can be saved by saving the __source__ attribute
of globals before termination.
Currently, you can define classes dynamically, and you can also save the source code of the class to a file in case you need it later.
> Moreover, in such a system
it is possible to modify the "code modification routines" and
eventually we have a self-modifying interface. Using a
program also means improving its usability.
Self-modifying source code is currently also possible. Just read the old source code from a .py file, modify it, and recompile it.
The current solution of using 'inspect' to get the source
code of functions is not adequate because it doesn't work
for code defined with "exec" and it doesn't have the source
of functions/classes defined in the interactive mode.
I fail to see why it isn't adequate. Anybody who wants to modify source code that was originally passed to exec just needs to preserve a copy of the source code, separately.
> Generally,
a "file" is something too abstract. What is more real is the
data received by the python parser and that is what is stored
in __source__.
Not at all. A file is precisely the level of granularity that is burnt into the Python language. A module is *always* a file, executed from top to bottom. It is not possible to recreate the source code of a module if you have only the source code of all functions, and all classes.
Regards, Martin _______________________________________________ Python-Dev mailing list [EMAIL PROTECTED] http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
