Hello, Let's say that I have those two facts in a pilog database:

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(be age (Paul 18)) (be age (Vincent 17)) I'm looking for the guy under 18 with this rule: (be underage (@X) (age @X @Y) (< @Y 18))

`If I ask (? (underage @X)) the result here is -> NIL where I expect to`

`get @X=Vincent.`

If I modify the above rule with: (be underage (@X) (age @X @Y) (equal @Y 18))

`The same query (? (underage @X)) now gives @X=Paul which is the expected`

`result.`

`I'm sure I'm missing something in the first case but I don't know what.`

`Any idea?`

Thanks, Eric -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe