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(emacs-lisp-intro.info)Regexp Review

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

`while'
     Repeatedly evaluate the body of the expression so long as the first
     element of the body tests true.  Then return `nil'.  (The
     expression is evaluated only for its side effects.)

     For example:

          (let ((foo 2))
            (while (> foo 0)
              (insert (format "foo is %d.\n" foo))
              (setq foo (1- foo))))
          
               =>      foo is 2.
                       foo is 1.
                       nil

     (The `insert' function inserts its arguments at point; the
     `format' function returns a string formatted from its arguments
     the way `message' formats its arguments; `\n' produces a new line.)

`re-search-forward'
     Search for a pattern, and if the pattern is found, move point to
     rest just after it.

     Takes four arguments, like `search-forward':

       1. A regular expression that specifies the pattern 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.

`let*'
     Bind some variables locally to particular values, and then
     evaluate the remaining arguments, returning the value of the last
     one.  While binding the local variables, use the local values of
     variables bound earlier, if any.

     For example:

          (let* ((foo 7)
                (bar (* 3 foo)))
            (message "`bar' is %d." bar))
               => `bar' is 21.

`match-beginning'
     Return the position of the start of the text found by the last
     regular expression search.

`looking-at'
     Return `t' for true if the text after point matches the argument,
     which should be a regular expression.

`eobp'
     Return `t' for true if point is at the end of the accessible part
     of a buffer.  The end of the accessible part is the end of the
     buffer if the buffer is not narrowed; it is the end of the
     narrowed part if the buffer is narrowed.

`prog1'
     Evaluate each argument in sequence and then return the value of the
     _first_.

     For example:

          (prog1 1 2 3 4)
               => 1