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- Path: sparky!uunet!pipex!bnr.co.uk!uknet!pavo.csi.cam.ac.uk!ag129
- From: ag129@cus.cam.ac.uk (Alasdair Grant)
- Newsgroups: bit.listserv.ibm-main
- Subject: Re: Is PL/S a dead language?
- Message-ID: <1992Dec28.180844.23066@infodev.cam.ac.uk>
- Date: 28 Dec 92 18:08:44 GMT
- References: <IBM-MAIN%92122809414050@RICEVM1.RICE.EDU>
- Sender: news@infodev.cam.ac.uk (USENET news)
- Organization: U of Cambridge, England
- Lines: 31
- Nntp-Posting-Host: bootes.cus.cam.ac.uk
-
- In article <IBM-MAIN%92122809414050@RICEVM1.RICE.EDU> "John A. Pershing Jr." <PERSHNG@YKTVMH.BITNET> writes:
- >The last I heard, no. I'm expecting the Beta drop of the next release
- >of the compiler Real Soon Now. This next release has lots of really
- >good stuff in it -- we really should market this *excellent* systems
- >programming language! (sigh...)
-
- From what I've seen of PL/S, it combines all the disadvantages of high-level
- languages (inability to get down to the bare machine instructions and
- system macros) with the disadvantages of assembler (inability to do global
- register allocation and inter-procedural optimisation). Most pieces of
- PL/S I've seen are full of RESPECIFY and references to real registers and
- real instructions. It even requires you to go to the machine instruction
- level to do compare-and-swap. A language that had built-in facilities for
- queue and counter management in a multitasking environment would be excellent,
- but PL/S isn't it.
-
- Now, if all MVS system functions were accessible as PL/S subroutines, that
- would be different, but they aren't. One has to use GENERATE all the time.
- Also, the way it generates calling sequences leaves something to be desired.
- I've seen lots of code like
-
- Myproc: PROCEDURE (A,B,C);
- CALL Another (A,B,C,1);
- END Myproc;
-
- - the overhead from this is greater than it would be with any other language.
-
- What I want to know is: why don't IBM use PL/1, and upgrade those features
- of PL/1 which aren't good enough? (Including the ability to do inline
- assembler, which any good C or Pascal compiler can do these days.)
- What can PL/S do that PL/1 never could? I'm genuinely curious.
-