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(emacs-lisp-intro.info)setcdr


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`setcdr'
========

   The `setcdr' function is similar to the `setcar' function, except
that the function replaces the second and subsequent elements of a list
rather than the first element.

   To see how this works, set the value of the variable to a list of
domesticated animals by evaluating the following expression:

     (setq domesticated-animals '(horse cow sheep goat))

If you now evaluate the list, you will be returned the list `(horse cow
sheep goat)':

     domesticated-animals
          => (horse cow sheep goat)

   Next, evaluate `setcdr' with two arguments, the name of the variable
which has a list as its value, and the list to which the CDR of the
first list will be set;

     (setcdr domesticated-animals '(cat dog))

If you evaluate this expression, the list `(cat dog)' will appear in
the echo area.  This is the value returned by the function.  The result
we are interested in is the "side effect", which we can see by
evaluating the variable `domesticated-animals':

     domesticated-animals
          => (horse cat dog)

Indeed, the list is changed from `(horse cow sheep goat)' to `(horse
cat dog)'.  The CDR of the list is changed from `(cow sheep goat)' to
`(cat dog)'.


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