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  1. has(link, sword).
  2. isWeapon(sword).
  3. hasWeapon(A) :- has(A, B), isWeapon(B).
Success #stdin #stdout 0.01s 68352KB
comments (?)
stdin 
hasWeapon(X).
stdout 
GNU Prolog 1.3.1
By Daniel Diaz
Copyright (C) 1999-2009 Daniel Diaz

X = link

yes
https://ideone.com/LVTWhm
language:
Prolog (gprolog 1.4.5)
created:
10 years ago
visibility:
secret

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