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(emacs-lisp-intro.info)cons & search-fwd Review

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Review
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   Here is a brief summary of some recently introduced functions.

`car'
`cdr'
     `car' returns the first element of a list; `cdr' returns the
     second and subsequent elements of a list.

     For example:

          (car '(1 2 3 4 5 6 7))
               => 1
          (cdr '(1 2 3 4 5 6 7))
               => (2 3 4 5 6 7)

`cons'
     `cons' constructs a list by prepending its first argument to its
     second argument.

     For example:

          (cons 1 '(2 3 4))
               => (1 2 3 4)

`nthcdr'
     Return the result of taking CDR `n' times on a list.  The `rest of
     the rest', as it were.

     For example:

          (nthcdr 3 '(1 2 3 4 5 6 7))
               => (4 5 6 7)

`setcar'
`setcdr'
     `setcar' changes the first element of a list; `setcdr' changes the
     second and subsequent elements of a list.

     For example:

          (setq triple '(1 2 3))
          
          (setcar triple '37)
          
          triple
               => (37 2 3)
          
          (setcdr triple '("foo" "bar"))
          
          triple
               => (37 "foo" "bar")

`progn'
     Evaluate each argument in sequence and then return the value of the
     last.

     For example:

          (progn 1 2 3 4)
               => 4

`save-restriction'
     Record whatever narrowing is in effect in the current buffer, if
     any, and restore that narrowing after evaluating the arguments.

`search-forward'
     Search for a string, and if the string is found, move point.

     Takes four arguments:

       1. The string to search for.

       2. Optionally, the limit of the search.

       3. Optionally, what to do if the search fails, return `nil' or an
          error message.

       4. Optionally, how many times to repeat the search; if negative,
          the search goes backwards.

`kill-region'
`delete-region'
`copy-region-as-kill'
     `kill-region' cuts the text between point and mark from the buffer
     and stores that text in the kill ring, so you can get it back by
     yanking.

     `delete-and-extract-region' removes the text between point and
     mark from the buffer and throws it away.  You cannot get it back.

     `copy-region-as-kill' copies the text between point and mark into
     the kill ring, from which you can get it by yanking.  The function
     does not cut or remove the text from the buffer.