Why is the argparse module so inflexible?

[Andrew Berg]

On 2013.06.27 08:08, Roy Smith wrote:
> Can you give us a concrete example of what you're trying to do?
The actual code I've written so far isn't easily condensed into a short simple snippet.
I'm trying to use argparse to handle all the little details of parsing and verifying arguments in the precmd hook for a cmd.Cmd child class.
argparse's help system is more sophisticated than cmd's help and does all the work of verifying arguments.
The problem I keep running into is that I can't handle any bad input very well. I would have to override every method that catches
ArgumentError in order to get a useful exception that I would then handle.
If I input something that begins with '-' that isn't recognized, parse_args doesn't even raise the exception; it just quits. In this case,
the message gets mangled if error is overridden, and I don't know why.

> You might look into "type=".  It's normally used for things like 
> "type=int" or "type=float", but it could give it any user-defined 
> function as a type and this essentially becomes a hook to insert your 
> own code into the middle of the processing.  Sometimes that can be 
> warped into doing all sorts of useful things.
I don't think that would solve my problem, but it would probably be quite useful.
-- 
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