PEP 285. Everything described in the PEP is here, and there is even
some documentation. I had to fix 12 unit tests; all but one of these
were printing Boolean outcomes that changed from 0/1 to False/True.
(The exception is test_unicode.py, which did a type(x) == type(y)
style comparison. I could've fixed that with a single line using
issubtype(x, type(y)), but instead chose to be explicit about those
places where a bool is expected.
Still to do: perhaps more documentation; change standard library
modules to return False/True from predicates.
In Include/, marshal.h declares both
PyMarshal_ReadLongFromFile()
and PyMarshal_ReadShortFromFile(),
but the second is missing from marshal.c.
[Shouldn't the return type be declared as 'short' instead of 'int'?
But 'int' is what was in marshal.h all those years... --Guido]
- Do not compile unicodeobject, unicodectype, and unicodedata if Unicode is disabled
- check for Py_USING_UNICODE in all places that use Unicode functions
- disables unicode literals, and the builtin functions
- add the types.StringTypes list
- remove Unicode literals from most tests.
Store floats and doubles to full precision in marshal.
Test that floats read from .pyc/.pyo closely match those read from .py.
Declare PyFloat_AsString() in floatobject header file.
Add new PyFloat_AsReprString() API function.
Document the functions declared in floatobject.h.
pickle.py
The code implicitly assumed that all ints fit in 4 bytes, causing all
sorts of mischief (from nonsense results to corrupted pickles).
Repaired that.
marshal.c
The int marshaling code assumed that right shifts of signed longs
sign-extend. Repaired that.
They're named as if public, so I did a Bad Thing by changing
PyMarshal_ReadObjectFromFile() to suck up the remainder of the file in one
gulp: anyone who counted on that leaving the file pointer merely at the
end of the next object would be screwed. So restored
PyMarshal_ReadObjectFromFile() to its earlier state, renamed the new greedy
code to PyMarshal_ReadLastObjectFromFile(), and changed Python internals to
call the latter instead.
The majority of the changes are in the compiler. The mainloop changes
primarily to implement the new opcodes and to pass a function's
closure to eval_code2(). Frames and functions got new slots to hold
the closure.
Include/compile.h
Add co_freevars and co_cellvars slots to code objects.
Update PyCode_New() to take freevars and cellvars as arguments
Include/funcobject.h
Add func_closure slot to function objects.
Add GetClosure()/SetClosure() functions (and corresponding
macros) for getting at the closure.
Include/frameobject.h
PyFrame_New() now takes a closure.
Include/opcode.h
Add four new opcodes: MAKE_CLOSURE, LOAD_CLOSURE, LOAD_DEREF,
STORE_DEREF.
Remove comment about old requirement for opcodes to fit in 7
bits.
compile.c
Implement changes to code objects for co_freevars and co_cellvars.
Modify symbol table to use st_cur_name (string object for the name
of the current scope) and st_cur_children (list of nested blocks).
Also define st_nested, which might more properly be called
st_cur_nested. Add several DEF_XXX flags to track def-use
information for free variables.
New or modified functions of note:
com_make_closure(struct compiling *, PyCodeObject *)
Emit LOAD_CLOSURE opcodes as needed to pass cells for free
variables into nested scope.
com_addop_varname(struct compiling *, int, char *)
Emits opcodes for LOAD_DEREF and STORE_DEREF.
get_ref_type(struct compiling *, char *name)
Return NAME_CLOSURE if ref type is FREE or CELL
symtable_load_symbols(struct compiling *)
Decides what variables are cell or free based on def-use info.
Can now raise SyntaxError if nested scopes are mixed with
exec or from blah import *.
make_scope_info(PyObject *, PyObject *, int, int)
Helper functions for symtable scope stack.
symtable_update_free_vars(struct symtable *)
After a code block has been analyzed, it must check each of
its children for free variables that are not defined in the
block. If a variable is free in a child and not defined in
the parent, then it is defined by block the enclosing the
current one or it is a global. This does the right logic.
symtable_add_use() is now a macro for symtable_add_def()
symtable_assign(struct symtable *, node *)
Use goto instead of for (;;)
Fixed bug in symtable where name of keyword argument in function
call was treated as assignment in the scope of the call site. Ex:
def f():
g(a=2) # a was considered a local of f
ceval.c
eval_code2() now take one more argument, a closure.
Implement LOAD_CLOSURE, LOAD_DEREF, STORE_DEREF, MAKE_CLOSURE>
Also: When name error occurs for global variable, report that the
name was global in the error mesage.
Objects/frameobject.c
Initialize f_closure to be a tuple containing space for cellvars
and freevars. f_closure is NULL if neither are present.
Objects/funcobject.c
Add support for func_closure.
Python/import.c
Change the magic number.
Python/marshal.c
Track changes to code objects.
the bug report (for details, look at it), but agree there's no need for Python
to declare atof itself: we #include stdlib.h, and ANSI C sez atof is declared
there already.
When reading a short, sign-extend on platforms where shorts are
bigger than 16 bits.
When reading a long, repair the unportable sign extension that was
being done for 64-bit machines (it assumed that signed right shift
sign-extends).
good C practice hasn't been available to everything all along.
Added Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) macro to pyport.h; this
just casts VALUE from type WIDE to type NARROW, but assert-fails if
Py_DEBUG is defined and info is lost due to casting.
Replaced a line in Fredrik's fix to marshal.c to use the new macro.
The depth field was never decremented inside w_object(), and it was
never initialized in PyMarshal_WriteObjectToFile().
This caused imports from .pyc files to fil mysteriously when the .pyc
file was written by the broken code -- w_object() would bail out
early, but PyMarshal_WriteObjectToFile() doesn't check the error or
return an error code, and apparently the marshalling code doesn't call
PyErr_Check() either. (That's a separate patch if I feel like it.)
As I really do not have anything better to do at the moment, I have written
a patch to Python/marshal.c that prevents Python dumping core when trying
to marshal stack bustingly deep (or recursive) data structure.
It just throws an exception; even slightly clever handling of recursive
data is what pickle is for...
[Fred Drake:] Moved magic constant 5000 to a #define.
This closes SourceForge patch #100645.
For more comments, read the patches@python.org archives.
For documentation read the comments in mymalloc.h and objimpl.h.
(This is not exactly what Vladimir posted to the patches list; I've
made a few changes, and Vladimir sent me a fix in private email for a
problem that only occurs in debug mode. I'm also holding back on his
change to main.c, which seems unnecessary to me.)
and lists; if the size is negative, raise an exception. Also raise an
exception when an undefined type is found -- all this to increase the
chance that garbage input causes an exception instead of a core dump.
be Ellipsis!).
Bumped the API version because a linker-visible symbol is affected.
Old C code will still compile -- there's a b/w compat macro.
Similarly, old Python code will still run, builtin exports both
Ellipses and Ellipsis.
Guido van Rossum
Neal Norwitz
Jeremy Hylton
Michael W. Hudson
Tim Peters
Martin v. Löwis
Fredrik Lundh
Thomas Wouters
Fred Drake