Expose gensym
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gensym Technical Terms
gensym: /jen'sim/ [from MacLISP for `generated symbol'] 1. v. To invent a new name for something temporary, in such a way that the name is almost certainly not in conflict with one already in use. 2. n. The resulting name. The canonical form of a gensym is `Gnnnn' where nnnn represents a number; any LISP hacker would recognize G0093 (for example) as a gensym. 3. A freshly generated data structure with a gensymmed name. These are useful for storing or uniquely identifying crufties (see {cruft}).