OWA_PATTERN regular expressions CHANGE function

Question

Hello,
I'm trying to use the CHANGE function to match an expression and then change the matched part of the string. The twist is that I would like to pass the matched part of the string through a function before it is replaced in the original string. Here is an example:
Pattern: 'C'
Text: 'CAAACAAAC'
Resulting text: 'DAAADAAAD'
Where the 'D' is the result of calling a function. The actual call to the OWA_PATTERN.CHANGE looks something like this:
OWA_PATTERN.CHANGE(mytext,'C',myfunction(&))
where the & argument to myfunction is as specified in the ORACLE docs as a reference to what was matched. The line of code doesn't work however. Anyone ever done anything like this?
Aziz 8)

Answer 1

SQL> CREATE OR REPLACE FUNCTION myfunction
  2    (p_pattern IN VARCHAR2)
  3    RETURN      VARCHAR2
  4  AS
  5  BEGIN
  6    RETURN CHR (ASCII (p_pattern) + 1);
  7  END myfunction;
  8  /
Function created.
SQL> CREATE OR REPLACE PROCEDURE test_pattern
  2    (pattern IN VARCHAR2,
  3     text    IN VARCHAR2)
  4  AS
  5    mytext      VARCHAR2 (256);
  6  BEGIN
  7    mytext := text;
  8    owa_pattern.change (mytext, pattern, myfunction (pattern), 'g');
  9    DBMS_OUTPUT.PUT_LINE ('Pattern:         ' || pattern);
10    DBMS_OUTPUT.PUT_LINE ('Text:            ' || text);
11    DBMS_OUTPUT.PUT_LINE ('Resulting text:  ' || mytext);
12  END test_pattern;
13  /
Procedure created.
SQL> SET SERVEROUTPUT ON
SQL> EXECUTE test_pattern ('C', 'CAAACAAAC')
Pattern:         C
Text:            CAAACAAAC
Resulting text:  DAAADAAAD
PL/SQL procedure successfully completed.