[Boost-users] [boost][format] How does one determine the number of format arguments?

Subject: [Boost-users] [boost][format] How does one determine the number of format arguments?
From: Neil Groves (neil_at_[hidden])
Date: 2009-07-21 08:57:34

Dear all,

Please accept my apologies if this ends up being a double post. I am having
trouble with posting to the boost mailing lists.

I have the need to obtain the number of 'arguments' (the %1% thingies!) in a
boost::format. Is this functionality supported in a manner that I have
failed to find in the documentation?

If it is not supported, would it be a worthwhile addition since it seems
easy to add assuming the num_args_ member variable is the information I
require and that validation code of boost::format instances is commonly very
useful. I have rarely executed error code that uses boost::format that is
difficult to test, but by adding a StringTable that loads at module startup
and wraps the boost format, I can provide compile-time validation of much of
the formatting code, and runtime validation of the format strings at module
startup. This would make it much easier to test.

Thank you for your time and consideration.

Regards,
Neil Groves