At 07:29 2019-05-19, Man-wai Chang changmw@gmail.com wrote:

You can just watch the value of variable f. A valid filter expression stored in variable f will not produce error.

What are you trying to do when you said "...would prefer just one statement.... in the heat of debugging"?

Trying to restrict the filter further.

[snip]

Sincerely,

Gene Wirchenko