More than once I coded short CLIST front-ends to ASM programs in order
to avoid IKJPARS while still doing the input processing you mentioned.
The clist would poke the results in a single string for the assembler
program to easily grab by offsets.
On 9/30/2021 7:37 PM, Skip Robinson wrote:
Even a dead horse needs a tail. Parsing CLIST parms involves more than
sorting out characters and delimiters. There are (my terminology) three
kinds of parms.
1. Positional parms
2. Keyword switch parms
3, Keyword value parms
Positional parms must come first in the order coded in the exec. Each
variable is assigned whatever value the user has entered.
Keyword switch parms must follow positional parms in any order. If the
keyword is present, the variable is assigned the value that matches the
variable name. 'Match' here means an unambiguous (sub)string. If the match
is ambiguous, CLIST prompts for an unambiguous.
Keyword value parms must also follow positional parms in any order, coded
like this: keyword(value). Value can be anything. Keyword entered by the
user must unambiguously match one coded in the CLIST, else CLIST prompts
the user.
So why the complexity? CLIST is very old, predating ISPF. Hence the user
had to supply lots of data at execution time. This framework offers
flexibility.
On Thu, Sep 30, 2021 at 4:14 PM Bob Bridges <robhbrid...@gmail.com> wrote:
I once wrote an external routine that can break a character string into
various individual parms and return them on the stack. It correctly parses
strings with quotes, parens and comment markers.
But as you say, even I hardly ever use it. Most routines work perfectly
well with a string of one-word arguments, and if I don't have to remember
what order they come in and don’t have to label them, anything more is
almost never required.
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* Having your book turned into a movie is like seeing your oxen turned
into bouillon cubes. -John LeCarré */
-----Original Message-----
From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf
Of Skip Robinson
Sent: Wednesday, September 29, 2021 18:06
....one of the most powerful features of CLIST is the mechanism by which
parameters/options are passed by the user: positional or keyword, required
or optional, with system prompting. I once saw a REXX routine that
simulated the old command/CLIST parm processing. It was very complicated
and hardly worth the trouble IMHO.
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