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.
This is the first batch of fixes that should be easy to verify based on context.
This fixes problem numbers: 220 (ast), 323-324 (symtable),
321-322 (structseq), 215 (array), 210 (hotshot), 182 (codecs), 209 (etree).
This was started by Mike Bland and completed by Guido
(with help from Neal).
This still needs a __future__ statement added;
Thomas is working on Michael's patch for that aspect.
There's a small amount of code cleanup and refactoring
in ast.c, compile.c and ceval.c (I fixed the lltrace
behavior when EXT_POP is used -- however I had to make
lltrace a static global).
