COBOL Manual for TNS/E Programs (H06.08+, J06.03+)

When multiple AFTER phrases appear, the mechanism is the same as for one AFTER phrase
except:
◦ In secondary AFTER phrases, vary-2 is also initialized with the value of base-2 in its
associated FROM phrase at the beginning of execution of the PERFORM statement.
◦ In the inner loop (as described earlier), the step “a cycle is performed” is replaced by
“execution proceeds to the next inner loop.”
◦ The logic of the next inner loop parallels that of the first inner loop except for:
– Its condition plays the role of condition-2.
– The next vary-2 is augmented by the current value of its step-2 after each cycle
is performed.
– The next vary-2 is initialized with the current value of the base-2 in its associated
FROM phrase when the value of its condition is TRUE.
After termination of a PERFORM statement with multiple AFTER phrases, vary-1 has the
value assigned, either by initialization or augmentation, at the point where the evaluation
of condition-1 gave a result of TRUE, and each vary-2 has the value assigned by
its last initialization from its associated base-2.
• Execution of PERFORM VARYING with TEST AFTER Specified
When no AFTER phrase list appears, vary-1 is initialized with the value of base-1 at the
beginning of execution of the PERFORM statement. The first cycle is then performed. After the
completion of each cycle, condition-1 is evaluated to determine whether or not to perform
another cycle. Whenever the evaluation of condition-1 results in TRUE, execution of the
statement terminates. If the evaluation of condition-1 results in FALSE, the value of vary-1
is augmented by the specified increment or decrement (the value of step-2 ), and another
cycle is performed.
After termination of the PERFORM statement, vary-1 has the value it contained at the end
of the last execution of the range of the PERFORM statement.
PERFORM 401