Glenn Wants To Know More Facts About Special Values

I found your article 10 Facts You Should Know about Special Values very interesting. I have a few questions related to a command I am writing.

–Glenn

I owe Glenn an apology. He is one of the many people whose email I never responded to. I’m sorry, Glenn. Sometimes life presents too many opportunities.

Here’s Glenn’s first question:

1. If a user specifies *ALL for a parameter, how do you prevent the user from typing in other values?

Fair enough. Define *ALL in the Single Value (SNGVAL) keyword, not in the Special Value (SPCVAL) keyword.

CMD        PROMPT('Do it')

PARM KWD(RPTTYPE) TYPE(*DEC) LEN(1) RSTD(*YES) +
     DFT(*ALL) +
     SPCVAL((*CVNPRB 1) (*LIBSUM 2) (*LIBDTL 3) +
            (*OBJSUM 4) (*OBJDTL 5)) +
     SNGVAL((*ALL 0)) +
     MIN(0) MAX(5) +
     PROMPT('Type of report')

Now you can run commands like these:

DOIT RPTTYPE(*ALL)
DOIT RPTTYPE(*LIBSUM *OBJSUM)
DOIT RPTTYPE(*CVNPRB *LIBSUM *LIBDTL *OBJSUM *OBJDTL)

But do this. . .

DOIT RPTTYPE(*ALL *LIBSUM)

. . .and you’ll get error CPD0094 (*ALL must be only value for parameter RPTTYPE).

Now, Glenn’s second question:

2. Can you prevent a user from keying in the same value more than once?

No. Nothing will stop you from doing this:

DOIT RPTTYPE(*LIBSUM *LIBSUM *LIBSUM *LIBSUM *LIBSUM)

The system allows you to enter up to five values in the RPTTYPE parameter. If you want to waste a spot by duplicating a value, the system won’t object. It is up to the command-processing program to recognize and ignore duplicates.

Glenn had two more questions, both of which deal with mixed lists. That will have to be a topic for another day.

–Ted

RELATED STORY

10 Facts You Should Know about Special Values

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