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programming - Searching linked lists that contain lists?


Following the advice I've read here and other sites, I've been trying to use the Mathematica equivalent of a linked lists...


testList = {{a, b}, {{c, d}, {{e, f}, {}}}}

Now, I want to see if {c,d} is a member of testList. How do I do that? MemeberQ doesn't transverse the list recursively and Flatten also nukes the sub lists. The following seems to work but I would expect there to be a cleaner simpler way...


memberInLinkedList[{}, _] = False;
memberInLinkedList[l_List, v_] := True /; First[l] == v;
memberInLinkedList[l_List, v_] := memberInLinkedList[Last[l], v];


Is there a more eloquent or built-in way to do this? Perhaps a general idiom or package that handles this transparently?



Answer



MemberQ[testList, {c, d}, Infinity]


True



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