How do i find the location of error: bad argument type: fixnump: nil
This morning I checked the ok variable that I set before I ran the program & it was nil. I then ran the code, typed in !ok at the command line and it was set to 12 so I was wrong about the variable not getting changed. o was looking at the watch console.
I'm not sure why its stopping there.it doesn't make much sense because this part of the code has always worked before.
[That should really have been in reply to @john.uhden rather than to me, but in any case....]
If it doesn't get as far as setting the 'ok' variable to 13, does it at least get as far as completing the definition of the PopListPick3 function? If you do something like:
(PopListPick3 "1")
[or with any text string representing an integer] does it give you a no-such-function error message?
[That is, assuming PopListPick3 is not in the localized variables list, so it will survive past the end of the routine.]
i apologize for that. I'm not sure I did this right but now I get this message when I select the region from the pull down on the dcl dialog box :
Command: stp Hard error occurred ***
internal stack limit reached (simulated)
If I don't select something in the dialog box it just gives me the same error I was getting before.
@marko_ribar wrote:
.... I won't do at beginning : (setq a nil b nil c nil ... )
I'd rather do : (mapcar '(lambda ( %%% ) (if %%% (set %%% nil))) '(a b c d ... [copy+paste what's from localization here] )))
Then when it breaks : (vl-some '(lambda ( %%% ) (setq $$$ (if (not $$$) 0 (1+ $$$))) (null %%%)) (list a b c d ... [ -||- ] )))
Then to see which one is nil - probably cause of error like you explained : (nth $$$ '(a b c d ... [ -||- ] )) => you get for ex. : W meaning this varibable is the alien...
A somewhat shorter way to achieve the same thing, without the need for the $$$ counter variable:
(setq vl '(a b c d)) ; list of variable names
(mapcar '(lambda (x) (if x (set x nil))) vl) ; set them all to nil
Then the routine proceeds, and let's say it manages to set values into the 'a' and 'b' variables, but fails in setting 'c', so that remains nil. This returns the name of the first nil variable, directly:
Command: (nth (vl-position nil (mapcar 'eval vl)) vl)
C
EDIT: BUT I'm now realizing that this won't always be a legitimate approach, because it depends on the expectation that all the variables should be set to non-nil values. But there are routines that legitimately set certain variables to nil -- for example, a routine working with a Polyline could have a variable that stores whether or not it's closed, with T or nil value. It would not be a failure for that variable to be nil, but in checking after a failure, the above approach would flag that one when the failure is actually somewhere later in the routine.
For that reason, I would still prefer the !-prefix check approach. As long as I'm aware of variables that could "successfully" get a nil value, I can check only those that should always have a non-nil value, until one of those is nil.
