Pathway/iTS SCREEN COBOL Reference Manual (G06.24+, H06.03+, Pathway/iTS 1.0+)

Procedure Division
Compaq NonStop™ Pathway/iTS SCREEN COBOL Reference Manual—426750-001
6-55
PERFORM Statements
add-routine.
MOVE 0 to flag.
:
: Once the add routine is successful, a 1 is moved
: to flag; otherwise, flag remains 0. As long as
: flag is 0, the procedure is reexecuted.
:
delete-routine.
PERFORM VARYING Statement
The PERFORM VARYING statement executes a procedure, or group of procedures as
established by the THROUGH phrase, while varying a data item until specified
conditions are true. When AFTER phrases are specified, the range is within a nested
loop. The innermost loop is defined by the last AFTER phrase; the outermost loop is
defined by the first set of parameters in the VARYING clause. When execution
completes, control passes to the statement following the PERFORM VARYING
statement.
proc-1 and proc-2
are the procedure paragraphs or sections to be executed.
vary-1 and vary-2
are the identifiers of integer numeric data items.
base-1 and base-2
are integer numeric literals or identifiers of numeric data items.
step-1 and step-2
are integer numeric literals or identifiers of numeric data items. Their value must
not be zero.
cond-1 and cond-2
are any conditional expressions.
The following example illustrates the PERFORM VARYING statement:
WORKING-STORAGE SECTION.
01 command-data.
05 FILLER PIC X(36) VALUE "ADD - ADD A NEW RECORD".
05 FILLER PIC X(36) VALUE "DELETE - DELETE A RECORD".
:
PERFORM proc-1 [ { THROUGH } proc-2 ]
[ { THRU } ]
VARYING vary-1 FROM base-1 BY step-1 UNTIL cond-1
[ AFTER vary-2 FROM base-2 BY step-2 UNTIL cond-2 ] ...