Suspected bug in -confirm-

[daniel klein]

The title is self-explanatory. Here is a reproducible example:

clear
sysuse auto
confirm variable , exact

There is no error where I think there should be one.

I think the above should be equivalent to

clear
sysuse auto
confirm variable

but it is not.

In case you are wondering, this is relevant in situations where you pass to confirm a local macro that might contain a variable name (or a variable list) but might also be empty. Something like

confirm `could_be_a_varname_or_empty' , exact

I am (still) using Stata 16.1 fully updated on Windows 11.


Edit:

Here is my workaround that I would like to share:

novarabbrev confirm variable ...

[Sebastian Kripfganz]

I can reproduce the example with fully-updated Stata 17 and I agree with Daniel that the expected behavior would be an error message when no variable name is specified, irrespective of whether the option exact is specified or not.

[William Lisowski]

Agree with #1 and #2 above, and - my interest aroused by the odd wording of the error message - point out that neither the option exact nor the existence of any data in memory is needed - just the comma that would precede any option.

. clear all

. confirm v
'' found where varname expected
r(7);

. confirm v ,

.

If this isn't considered a bug, and can't be explained as a feature, correcting it as an inconsistency is a good candidate for the Stata 18 wish list.