The member and contains commands determine whether or not an object is in a list; the difference between them is the order of the arguments (required for compatibility reasons).
| member(2,[0,1,2,3,4,2]) | 
or:
| member(2,%{0,1,2,3,4,2%}) | 
or:
| contains([0,1,2,3,4,2],2) | 
or:
| contains(%{0,1,2,3,4,2%},2) | 
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