Thanx Stefan for the fix.
Since there's some interest in this, I've migrated the code to GitHub and added a baseline.
So,  Stefan you can add your fix and make a PR :-)

Noury

On Nov 6 2020, at 3:58 pm, St��phane Ducasse <stephane.ducasse@inria.fr> wrote:
Hi stephan did you publish the code?

On 6 Nov 2020, at 15:12, stephan <stephan@stack.nl> wrote:

Replacing BTNGVariable>>#nextValue by

nextValue
    | nextValue |
    self currentValue
        ifNotNil: [valuesToExplore remove: self currentValue].
    nextValue := self valuesToExplore ifEmpty: [ nil ]
                ifNotEmpty: [self valuesToExplore anyOne].
    self currentValue: nextValue.
    ^ nextValue

returning nil instead of self when there are no more new values
makes the tests pass in BackTalkNG-Noury.20.mcz (Pharo 9)

That version looks like it is work in progress but has one working
solver.

Stephan


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