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04/25/15: beazley
If PLY is unable to create the 'parser.out' or 'parsetab.py' files due
to permission issues, it now just issues a warning message and
continues to operate. This could happen if a module using PLY
is installed in a funny way where tables have to be regenerated, but
for whatever reason, the user doesn't have write permission on
the directory where PLY wants to put them.
04/24/15: beazley
Fixed some issues related to use of packages and table file
modules. Just to emphasize, PLY now generates its special
files such as 'parsetab.py' and 'lextab.py' in the *SAME*
directory as the source file that uses lex() and yacc().
If for some reason, you want to change the name of the table
module, use the tabmodule and lextab options:
lexer = lex.lex(lextab='spamlextab')
parser = yacc.yacc(tabmodule='spamparsetab')
If you specify a simple name as shown, the module will still be
created in the same directory as the file invoking lex() or yacc().
If you want the table files to be placed into a different package,
then give a fully qualified package name. For example:
lexer = lex.lex(lextab='pkgname.files.lextab')
parser = yacc.yacc(tabmodule='pkgname.files.parsetab')
For this to work, 'pkgname.files' must already exist as a valid
Python package (i.e., the directories must already exist and be
set up with the proper __init__.py files, etc.).