/sys$common/syshlp/TPUHELP.HLB  —  SPANL
  SPANL

     Creates a pattern matching the longest possible string containing
     characters that are in the specified string, range, or buffer.  A
     pattern created with SPANL can match text containing line breaks.

  Syntax

     pattern := SPANL ({string | range | buffer} [, {FORWARD | REVERSE}])

     Parameters

     string               A string containing the characters that TPU is
                          to match in the searched text.

     range                A range containing the characters that TPU is
                          to match in the searched text.

     buffer               A buffer containing the characters that TPU is
                          to match in the searched text.

     FORWARD              A keyword directing TPU to match characters in
                          the forward direction.

     REVERSE              A keyword directing TPU to match characters as
                          follows:  First, match characters in the forward
                          direction until TPU finds a character that is
                          not a member of the set of characters in the
                          specified buffer, range, or string.  Next, return
                          to the first character that SPANL matched and
                          start matching characters and line ends in the
                          reverse direction until TPU finds a character
                          not in the specified buffer, range, or string.
                          You can specify REVERSE only if you are using
                          SPANL in the first element of a pattern being used
                          in a reverse search.  In other contexts,
                          specifying REVERSE has no effect.

                          The behavior enabled by REVERSE allows an
                          alternate form of reverse search.  By default, a
                          reverse search stops as soon as a successful match
                          occurs, even if there might have been a longer
                          successful match in the reverse direction.  By
                          specifying REVERSE with SPANL, you direct TPU
                          not to stop matching in either direction until it
                          has matched as many characters as possible.

  Comments

     SPANL matches one or more characters, each of which must appear in the
     string, range, or buffer passed as the parameter, and one or more line
     breaks.  To match one or more line breaks and nothing else, specify a
     null string as a parameter to SPANL.

  Examples

     1.  pat1 := SPANL ("1234567890");

         Creates a pattern matching any number and sequence of contiguous
         digits on one or more lines.

     2.  pat1 := SPANL ("1234567890", FORWARD);

         This statement has exactly the same effect as Example 1.

     3.  pat1 := SPANL (" ");

         Stores a pattern in the variable "pat1" matching the longest
         sequence of blank characters starting at the current character
         position and continuing to an end-of-search condition.

     4.  vowel_pattern := SPANL ('aeiouy', REVERSE);

         This statement defines the variable "vowel_pattern" to mean the
         longest string of characters that are all vowels.  If you use the
         following statement:

         the_range := SEARCH (vowel_pattern, REVERSE);

         when the cursor is on the "a" in the word "liaison", then the
         variable "the_range" contains the string "iai".  This is because
         when you use SPANL with REVERSE as the first element of a pattern,
         and then use that pattern in a reverse search, SPAN matches as many
         characters as possible in both the forward and reverse directions.

         If the cursor is on the "a" but you define the variable
         "vowel_pattern" without the REVERSE keyword, like this:

         vowel_pattern := SCAN ('aeiouy');

         and then do a reverse search, "the_range" contains the string "ai",
         showing that the search matched from the starting point forward but
         did not return to the starting point to match backward as well.

  Related Topics

  ANCHOR       ANY        ARB              MATCH     NOTANY     SCAN
  SCANL        SEARCH     SEARCH_QUIETLY   SPAN      UNANCHOR
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