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Author v+python
Recipients paul.j3, v+python
Date 2014-06-07.19:55:40
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Yes, I hope someday the parse_intermixed_args patch can be released... but I know it is not relevant to this issue.

I was aware of the %(substitution_variables) in the default help formatter, but I (1) goofed and entered % without escaping it (2) was surprised at how unhelpful the Traceback was at isolating the problem.

Happily, my code had only a few instances of %) so I was able to isolate it fairly quickly, but the error report certainly shows up at quite a distance (execution-wise) from the location of the source bug.

I haven't looked at the source for the HelpFormatter code: if it concatenates all the help text and then does substitutions en masse, then it would be difficult to isolate the error to a particular argument. If, on the other hand, it loops through the help text for each argument, doing the substitutions, and later formatting and concatenating, then surrounding the substitution attempt with a try: block so that the name of the argument with the faulty help text could be reported, that would be a big help to this situation, at little cost.
Date User Action Args
2014-06-07 19:55:41v+pythonsetrecipients: + v+python, paul.j3
2014-06-07 19:55:41v+pythonsetmessageid: <>
2014-06-07 19:55:41v+pythonlinkissue21666 messages
2014-06-07 19:55:40v+pythoncreate