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  • Subin Velleringatt thinks this is interesting:

eq can also be used to compare conses (the links created by the cons command). However, it returns true values only when a cons is compared directly to itself, created by the same cons call. This means, two unrelated conses that “look” exactly the same can fail an eq test. Since eq can check a cons cell only against itself, using eq with conses isn’t really that useful for a beginner. However, an advanced Lisper may want to compare conses with eq under certain circumstances

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Cover of Land of Lisp

Note

Confusing