lnotab-based tracing is very complicated and isn't documented very well. There
were at least 3 comment blocks purporting to document co_lnotab, and none did a
very good job. This patch unifies them into Objects/lnotab_notes.txt which
tries to completely capture the current state of affairs.
I also discovered that we've attached 2 layers of patches to the basic tracing
scheme. The first layer avoids jumping to instructions that don't start a line,
to avoid problems in if statements and while loops. The second layer
discovered that jumps backward do need to trace at instructions that don't
start a line, so it added extra lnotab entries for 'while' and 'for' loops, and
added a special case for backward jumps within the same line. I replaced these
patches by just treating forward and backward jumps differently.
Most uses of PyCode_Addr2Line
(http://www.google.com/codesearch?q=PyCode_Addr2Line) are just trying to get
the line number of a specified frame, but there's no way to do that directly.
Forcing people to go through the code object makes them know more about the
guts of the interpreter than they should need.
The remaining uses of PyCode_Addr2Line seem to be getting the line from a
traceback (for example,
http://www.google.com/codesearch/p?hl=en#u_9_nDrchrw/pygame-1.7.1release/src/base.c&q=PyCode_Addr2Line),
which is replaced by the tb_lineno field. So we may be able to deprecate
PyCode_Addr2Line entirely for external use.
If anyone wants to clean up the documentation, feel free. It's my first documentation foray, and it's not that great.
Will port to py3k with a different strategy.
- simplify parsing and printing of complex numbers
- make complex(repr(z)) round-tripping work for complex
numbers involving nans, infs, or negative zeros
- don't accept some of the stranger complex strings
that were previously allowed---e.g., complex('1..1j')
int, long, and float __format__(), and it keeps their implementation
in sync with py3k.
Also added PyOS_double_to_string. This is the "fallback" version
that's also available in trunk, and should be kept in sync with that
code. I'll add an issue to document PyOS_double_to_string in the C
API.
There are many internal cleanups. Externally visible changes include:
- Implement PEP 378, Format Specifier for Thousands Separator, for
floats, ints, and longs.
- Issue #5515: 'n' formatting for ints, longs, and floats handles
leading zero formatting poorly.
- Issue #5772: For float.__format__, don't add a trailing ".0" if
we're using no type code and we have an exponent.
Re http://bugs.python.org/issue4315
The symbol table used the same name dictionaries to recursively
analyze each of its child blocks, even though the dictionaries are
modified during analysis. The fix is to create new temporary
dictionaries via the analyze_child_block(). The only information that
needs to propagate back up is the names of the free variables.
Add more comments and break out a helper function. This code doesn't
get any easier to understand when you only look at it once a year.
POP_JUMP_IF_{TRUE,FALSE} and JUMP_IF_{TRUE,FALSE}_OR_POP. This avoids executing
a POP_TOP on each conditional and sometimes allows the peephole optimizer to
skip a JUMP_ABSOLUTE entirely. It speeds up list comprehensions significantly.