Re: Fortran 77 parser

Ron Shepard wrote:
In article <w_2dnQHZlOITOGranZ2dnUVZ_oaonZ2d@xxxxxxxxxxxxx>,
Walter Spector <w6ws_xthisoutx@xxxxxxxxxxxxx> wrote:

... people using Crays
tended to use standard conforming declarations more often. (Maybe
because they got burned by REAL*n not being what they expected?
I don't recall much use of that form either, although I know that
was permitted. Mostly eveyone was actively advosed not to use it.)

Many people using Crays, at least in the early days, had migrated
from 60-bit CDC gear. CDC did not support the IBM-ish *n notation.
So there was never a legacy of using it for double precision.

The above comments may have been true for people using Crays and
nothing else. But when I started using Cray computers (about 1983),
I was concerned about portability of the code to a fairly wide range
of computers (including 60-bit CDCs, IBM mainframes, minicomputers
of various architectures, 36-bit DEC and Univac computers, attached
processors, etc.). In my situation, using real*8 declarations was
the best way to ensure portable code. Every compiler I used
supported those declarations, [...]

Except the CDC you mentioned. By then CDC was struggling.
Still, it wasn't inevitable that the ETA wouldn't pull the fat out
of the fire.

Or is it that there *was* a CDC compiler that made REAL*8
into a default 60-bit? (Eight whats?) Actually Walt Spector's
statement about CDC matches my own (admittedly faulty) memory
of the issue: CDC didn't support REAL*n.

Remember in 1983, even utility programs such as Lex and Yacc, things
used in general by computer scientists but never touched by
scientists and engineers, were written in fortran and produced
fortran code. [...]

Of course they weren't *called* Lex and Yacc. I've used LRSYS
(which could generate parsers in LRLTRAN, Fortran (77), and
Pascal. I think they added C a few years later. By 1991 is supported
two or three more languages.

--
J. Giles

"I conclude that there are two ways of constructing a software
design: One way is to make it so simple that there are obviously
no deficiencies and the other way is to make it so complicated
that there are no obvious deficiencies." -- C. A. R. Hoare


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