Error: Attribute z not found in relation definition. in file keys.dl at line 11
.decl rel2(x:symbol, y:symbol) choice-domain (x, z)
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Error: Attribute z not found in relation definition. in file keys.dl at line 14
.decl rel3(x:symbol, y:symbol) choice-domain z
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Error: Attribute z not found in relation definition. in file keys.dl at line 17
.decl rel4() choice-domain z
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3 errors generated, evaluation aborted
