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cdr
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/ku'dr/ or /kuh'dr/ [LISP] To skip past the first item from a
list of things (generalised from the LISP operation on binary
tree structures, which returns a list consisting of all but
the first element of its argument). In the form "cdr down",
to trace down a list of elements: "Shall we cdr down the
agenda?" Usage: silly. See also loop through.
Historical note: The instruction format of the IBM 7090 that
hosted the original LISP implementation featured two 15 bit
fields called the "address" and "decrement" parts. The term
"cdr" was originally "Contents of Decrement part of Register".
Similarly, "car" stood for "Contents of Address part of
Register".
The cdr and car operations have since become bases for
formation of compound metaphors in non-LISP contexts. GLS
recalls, for example, a programming project in which strings
were represented as linked lists; the get-character and
skip-character operations were of course called CHAR and CHDR.