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The `re-search-forward' Function
================================

   The `re-search-forward' function is very like the `search-forward'
function.  (Note: The `search-forward' Function.)

   `re-search-forward' searches for a regular expression.  If the
search is successful, it leaves point immediately after the last
character in the target.  If the search is backwards, it leaves point
just before the first character in the target.  You may tell
`re-search-forward' to return `t' for true.  (Moving point is therefore
a `side effect'.)

   Like `search-forward', the `re-search-forward' function takes four
arguments:

  1. The first argument is the regular expression that the function
     searches for.  The regular expression will be a string between
     quotations marks.

  2. The optional second argument limits how far the function will
     search; it is a bound, which is specified as a position in the
     buffer.

  3. The optional third argument specifies how the function responds to
     failure: `nil' as the third argument causes the function to signal
     an error (and print a message) when the search fails; any other
     value causes it to return `nil' if the search fails and `t' if the
     search succeeds.

  4. The optional fourth argument is the repeat count.  A negative
     repeat count causes `re-search-forward' to search backwards.

   The template for `re-search-forward' looks like this:

     (re-search-forward "REGULAR-EXPRESSION"
                     LIMIT-OF-SEARCH
                     WHAT-TO-DO-IF-SEARCH-FAILS
                     REPEAT-COUNT)

   The second, third, and fourth arguments are optional.  However, if
you want to pass a value to either or both of the last two arguments,
you must also pass a value to all the preceding arguments.  Otherwise,
the Lisp interpreter will mistake which argument you are passing the
value to.

   In the `forward-sentence' function, the regular expression will be
the value of the variable `sentence-end', namely:

     "[.?!][]\"')}]*\\($\\|  \\|  \\)[
     ]*"

The limit of the search will be the end of the paragraph (since a
sentence cannot go beyond a paragraph).  If the search fails, the
function will return `nil'; and the repeat count will be provided by
the argument to the `forward-sentence' function.