First, it appears that warnings::warn will always warn (write to standard error) and only uses the caller's warn setting to die vs. warn, not to not warn. While warnings::warnif will add the warning enable/disable.

However, what we really want, I think, is carp rather than a warn, respecting the caller's settings.

If you write 

if (warnings::enabled())
 {
 carp "check your argument";
 }

[download]
that still does nothing about the possibility that the caller set that category to FATAL. Furthermore, there is warnings::enabled but no indication of FATAL! This seems to be an oversight.

So, how can we use the warnings features in a module to best effect? Does anybody really use it?

—John

In reply to warnings::warnif etc. wise usage? by John M. Dlugosz

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