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(emacs-lisp-intro.info)car cdr & cons

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`car', `cdr', `cons': Fundamental Functions
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   In Lisp, `car', `cdr', and `cons' are fundamental functions.  The
`cons' function is used to construct lists, and the `car' and `cdr'
functions are used to take them apart.

   In the walk through of the `copy-region-as-kill' function, we will
see `cons' as well as two variants on `cdr', namely, `setcdr' and
`nthcdr'.  (Note: copy-region-as-kill.)

Strange Names

An historical aside: why the strange names?

car & cdr

Functions for extracting part of a list.

cons

Constructing a list.

nthcdr

Calling `cdr' repeatedly.

nth

setcar

Changing the first element of a list.

setcdr

Changing the rest of a list.

cons Exercise