Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!mcsun!ukc!dcl-cs!aber-cs!pcg
From: pcg@aber-cs.UUCP (Piercarlo Grandi)
Newsgroups: comp.lang.misc
Subject: Re: Late Bloomers Revisited
Message-ID: <1518@aber-cs.UUCP>
Date: 19 Dec 89 19:29:17 GMT
Reply-To: pcg@cs.aber.ac.uk (Piercarlo Grandi)
Organization: Dept of CS, UCW Aberystwyth
	(Disclaimer: my statements are purely personal)
Lines: 70


In article <1989Dec18.192301.3863@ico.isc.com> rcd@ico.isc.com (Dick Dunn) writes:
    
    > In Europe, two landmark events happened; Dahl, Dijkstra, Hoare
    > authored "Structured Programming"...
    
    You need to be careful about that one, because the three parts of _Struc-
    tured_Programming_ have different origins and different real dates.

Well, they all were presented at the NATO workshops, didn't they? certainly
they are utterly different in flavour. The Hoare and the Dahl contributions,
about type systems and non nested flow control, have unfortunately been
mostly forgotten.

    Pascal was a result of the war, not the precipitator.  There were several
    candidate language proposals presented to WG2.1, and after very heated
    dispute (Grandi calls it a "small war"; I would omit "small":-), those
    favoring a simple language produced a sort of "minority report" and
    eventually left the group.  Pascal followed shortly thereafter.

Well, Pascal as we know it today. Let's say I used "Pascal" with some
latitude here, to mean the coagulation of the ideas from Hoare's work on
typing, and from Wirth's work on PL/360 and Algol W. Indeed Pascal was the
answer to Algol 68, and unfortunately more or less buried it. This happened
because, I reckon, a free model implementation was readily available, and
quickly adopted at many Universities.

The Algol 68 guys had painted themselves in a corner, because they had
relied on advances in the state of the art in compilers to make Algol 68
implementable and usable. This took quite a few years, not unlike Ada, but
for different reasons. I really think that some aspects of Algol 68 (user
defined priorities and operator symbols, operators and modes with the same
name, excessive overloading of parenthesis, ...) were a very poor tradeoff
between language sophistication and cost of compilation, especially as to
syntax. At least however Algol 68 *semantics* were carefully designed to be
efficiently implementable, and by and large they were. I think that the bits
of Algol 68 that went into C++ have been admirably chosen, and Stroustrup
has got it more right.

The end result is that there are nowadays some excellent (and portable)
Algol 68 compilers, like Algol 68C, RSRE, FLACC, and a few others, and some
pretty good subset compilers (Manchester for ACK, a British/Canadian one for
PDPs, ...). The reader of this newsgroup already knows I wish some were
posted to the net...

    That's what we know now as the "Bourne shell" - but this appeared circa
    Version 7, which is very late 70's.  The Bourne shell was by no means the
    first /bin/sh.

Unfortunately. I always reckoned myself lucky I did serious work on Unix
only starting with V7 (can you say "Onyx"? even PDPs were too expensive...).
The older shell was almost terrible.
    
    I wonder if some of the influences from Algol 68, and more particularly
    from Mary (a wonderful bit of work) could have come via Mark Rain, who
    was deeply involved in Mary and at least peripherally involved in both
    Algol 68 and Green.

Well, Mary certainly influenced LIS, judging from the latter's syntax and
certain aspects of semantics. I read some papers about Mary in some old
Machine Oriented HL Language proceedings, and given that LIS is also
described as a MOHLL, I am sure that Ichbiah did his homework and was well
aware of Mary.

By he way, are these MOHLL conferences still held? They were *very*
interesting.
-- 
Piercarlo "Peter" Grandi           | ARPA: pcg%cs.aber.ac.uk@nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcvax!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk