MODULE 7 · WORKING WITH TEXT · 3/8

Building text with STRING

14 min30 XPExercise

STRING joins several pieces of text into one field. Each piece says how much of it to use with a DELIMITED BY phrase:

       IDENTIFICATION DIVISION.
       PROGRAM-ID. STRDEMO.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  WS-FIRST     PIC X(10) VALUE "GRACE".
       01  WS-LAST      PIC X(10) VALUE "HOPPER".
       01  WS-FULL      PIC X(30).
       PROCEDURE DIVISION.
           MOVE SPACES TO WS-FULL
           STRING WS-LAST  DELIMITED BY SPACE
                  ", "     DELIMITED BY SIZE
                  WS-FIRST DELIMITED BY SPACE
                  INTO WS-FULL
           END-STRING
           DISPLAY "[" WS-FULL "]"
           STOP RUN.

Output:

[HOPPER, GRACE                 ]

DELIMITED BY SIZE copies the whole item, trailing spaces and all.
DELIMITED BY SPACE copies up to (not including) the first space. That is how you drop the padding from a fixed-width field.
DELIMITED BY any literal or data item stops at that text.

If the delimiter never appears, the whole item is copied.

STRING does not clear the target

STRING writes only the bytes it transfers. Whatever was in the rest of the receiving field stays there. Forget the MOVE SPACES and you get this:

       IDENTIFICATION DIVISION.
       PROGRAM-ID. STRDIRTY.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  WS-OUT       PIC X(12) VALUE "XXXXXXXXXXXX".
       PROCEDURE DIVISION.
           STRING "ABC" DELIMITED BY SIZE INTO WS-OUT
           DISPLAY "[" WS-OUT "]"
           STOP RUN.

Output: [ABCXXXXXXXXX]. Always initialise the target first.

Names with spaces in them

DELIMITED BY SPACE breaks on VAN DYKE or NEW YORK: you get VAN. The usual fix is to delimit by two spaces, DELIMITED BY " ". A single space inside the value is kept, while the run of padding after it ends the copy. (A value that fills its field completely has no padding, and is simply copied whole.)

WITH POINTER

A pointer is a numeric field holding the next position to write in the target. STRING starts there and leaves it pointing just past the last byte written. That lets you build a field in several steps, and it tells you how long the result is:

       IDENTIFICATION DIVISION.
       PROGRAM-ID. STRPTR.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  WS-LINE      PIC X(30).
       01  WS-PTR       PIC 9(2).
       PROCEDURE DIVISION.
           MOVE SPACES TO WS-LINE
           MOVE 1 TO WS-PTR
           STRING "ACCT " DELIMITED BY SIZE
                  INTO WS-LINE WITH POINTER WS-PTR
           STRING "00123" DELIMITED BY SIZE
                  INTO WS-LINE WITH POINTER WS-PTR
           DISPLAY "[" WS-LINE "] NEXT: " WS-PTR
           STOP RUN.

Output: [ACCT 00123 ] NEXT: 11. Ten bytes were written, so the pointer is 11. The length of what you built is pointer - 1.

ON OVERFLOW

If the pieces do not fit, STRING stops at the end of the target and the rest is lost. Add ON OVERFLOW to find out:

           STRING ... INTO WS-SHORT
               ON OVERFLOW DISPLAY "NAME TRUNCATED"
           END-STRING

On the job

STRING shows up wherever a program produces text for humans or other systems: names on statements, address lines, email bodies, CSV extracts. Reviewers look for two things: a MOVE SPACES (or INITIALIZE) before it, and an ON OVERFLOW wherever the data could be longer than expected.

Your task

The customer letters program needs a one-line name and address label. Read three lines from input into the fields the starter declares:

First name (WS-FIRST, PIC X(15))
Last name (WS-LAST, PIC X(20))
City (WS-CITY, PIC X(15))

Build the label in WS-LABEL with a single STRING statement using WITH POINTER, then display it, followed by its length (pointer - 1):

LABEL: HOPPER, GRACE (ARLINGTON)
LENGTH: 25

Last names and cities can contain a single space, such as VAN DYKE or NEW YORK, and must come out whole.

← Reference modification Splitting text with UNSTRING →

Run your program to see its output here. The first visible test's input and datasets are used.

Submit to grade your program against every test.