On Sun, 7 Apr 2013 09:51:48 -0400, Peter Relson wrote:
>>ISPF also supports sequence numbers for RECFM=VB; I hope that
>>you're not saying that those are not stripped when FB
>>sequence numbers are.
>
>That is exactly what I am saying. I suppose it comes down to: if it hurts
>to do that, then don't do that.
>
I agree. I dislike sequence numbers anyway.
>The rules will be documented. As with most things, you get to decide what
>that implies to your usage.
>
I see three main levels of implementation quality.
1) The function is incomplete.
2) The Turing Tarpit in which everything is possible but nothing
of interest is easy. -- Alan Perlis.
3) Functional completeness with user friendliness.
The PARMDD rules, like much of JCL, (will) fall squarely in category
(2). Circa 1964, there was an excuse: IBM was in a desperate
rush to get OS/360 out the door and into revenue. Things _should_
be different in the 21st Century. z/OS is vastly more complex than
OS/360 and proportionally more consideration should have been
given to usability.
>Regarding stripping of trailing blanks:
>>Imagine RECFM=VB.
>Of course in many RECFM=VB cases there are no trailing blanks, the record
>length having been set to reflect the result of stripping off trailing
>blanks.
>
In many other cases, there are trailing blanks and the programer
considers them to be significant. That's why ISPF has a PRESERVE
option. The PARMDD rules appear to thwart the programmers'
and ISPF's intent here.
The challenge of functional completeness: Design an algorithm
which accepts as input any character string of no more than
32760 characters and produces as output a data set which
when referenced as PARMDD passes _exactly_ that string as the
input to the JCL symbol substitution mechanism. (If PARMDD
is instream, it may be necessary to use DD DATA,DLM='..'.)
Is your algorithm a Turing Tarpit?
-- gil
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