[Python-Dev] [Python-checkins] commit of r41880 - python/trunk/Python/Python-ast.c (original) (raw)

Tim Peters tim.peters at gmail.com
Tue Jan 3 19:58:52 CET 2006

[Jeremy Hylton]

I think this solution is better. It's relatively rare for people to change the ast definition, so for most purposes these should be static files.

[Martin v. Löwis]

Interestingly enough, I found yesterday that Python-ast.c did change for me, even though I had not touched the AST grammar at all. Assuming somebody forgot to commit this file, I just did.

I now investigated where this change originated from, and it was this commit r41812 | tim.peters | 2005-12-26 00🔞31 +0100 (Mo, 26 Dez 2005) | 2 lines Whitespace normalization. This indicates two problems: apparently, the whitespace normalization also normalizes string literals; not sure whether this is a good idea or not.

reindent.py never leaves a hard tab character behind, or a line with trailing whitespace. Those are features, because they're invisible, and someone's editor is going to destroy either or both of those sooner or later anyway. No core code should rely on them (inside string literals or not).

I don't believe that asdl_c.py requires either hard tab characters or trailing whitespace on lines (both of which reindent.py replaced/removed), and reindent.py's output is a fixed-point for reindent.py, so those shouldn't happen again (unless/until someone sticks hard tabs or trailing whitespace into asdl_c.py again).

If someone is really keen to have hard tab characters inside the CODE strings written by this file, then "the right" way to do that is to use \t escapes inside the triple-quoted strings (instead of using embedded hard tab characters).

Furthermore, people should be made aware that something deserves their attention when they find that Python-ast.c has changed for them (but I guess Tim never saw Python-ast.c change, because this build step isn't executed on Windows).

I can do better than guess about that ;-)

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