#87 oclingo: unsafe variables message


We invoke the following command with oclingo and we get the command that appears below:

dhcp-64-103-84-154:oclingo dmagka$ oclingo dpal/cp_base.lp dpal/o_transforms.lp --imax=9 0 &
[1] 7711
dhcp-64-103-84-154:oclingo dmagka$
ERROR: unsafe variables in:
dpal/o_transforms.lp:4:1: c(X):-a(X),r(X,Y),b(Y).
dpal/o_transforms.lp:4:11: X
dpal/o_transforms.lp:4:19: Y

Why are X and Y considered unsafe since they both occur in the positive body of the rule?
This is in contrast with what potasco guide says "gringo expects rules to be safe, i.e., all variables that appear in a rule have to appear in some positive literal (a literal not preceded by not) in the body".

Files cp_base.lp and o_transforms.lp attached.

1 Attachments


  • Philipp Obermeier

    I ran oclingo on cb_base.lp and rule 'c(X):-a(X),r(X,Y),b(Y).' w/o any safety errors. Can you pls also attach o_transforms.lp.

  • Crispin Dent-Young

    Hi Phillip,

    I'm sorry - please look at ticket #89 - we opened this ticket and #88 sort of by accident - and we could not figure out how to delete them. #89 should have the correct description and information.

    Thanks (and sorry)


  • Roland Kaminski

    Roland Kaminski - 2014-04-24
    • status: open --> wont-fix
  • Roland Kaminski

    Roland Kaminski - 2014-04-24

    oclingo development is discontinued - please switch to clingo-4


Log in to post a comment.