gm2
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Gm2] Issue with rename a function & compiler crash


From: Fischlin Andreas
Subject: Re: [Gm2] Issue with rename a function & compiler crash
Date: Mon, 12 Mar 2018 13:30:45 +0000

Dear Gaius,

Sounds like a great idea.

Regards,
Andreas


On 12/03/2018, at 12:20, Gaius Mulley <address@hidden> wrote:

"Fischlin  Andreas" <address@hidden> writes:

Dear all, 

AFAIK your interpretation is right.

However, to make for once a comment on the bad habit of gm2
programmers to NOT capitalize procedures and types is really a very
big drawback of gm2. Just to say it once. To give an example, the
discussed code should have been coded as follows:

MODULE Test ;

CONST
foo = Bar ;

PROCEDURE Bar (ch: CHAR) : CHAR ;
BEGIN
RETURN CAP (ch)
END Bar ;

VAR
ch: CHAR ;

BEGIN
ch := foo ('a')
END Test.

In general the rules used by M2 programmers at ETH Zurich since its
invention are:

types Start always with upper case - use class names
constants and variables Start always with lower case - noun or
adjective + type name
function procedures Start as procedures always with upper case -
otherwise same rule as for variables
procedures (modules) Start always with upper case - use a verb

One of the biggest advantages is that basic types can be deduced
naturally from the identifier, since capitalized are types or
procedures, but the latter use verbs (only exception are function
procedures) while types use class names. Lower case identifiers are a
constant or variable, which can typically used interchangeably. These
are the rules we have been following in general at ETH Zurich by all
those programmers working in close collaboration with Niklaus Wirth
and we never regretted following these rules. It is a pity gm2 code
has unfortunately AFAIK largely ignored these very helpful
conventions. Some arguments are nicely discussed in Keller (1990), but
we do not capitalize, e.g. constants, as Keller writes. But Keller
(1990) nicely explains the philosophy behind using nouns vs. verbs
etc.

Regards,
Andreas

Cited References:
------------------------
Keller, D., 1990. A guide to natural naming. ACM, 25: 95-102. doi:
10.1145/382080.382637 Ke183


Hi Andreas,

many thanks for pointing me in this direction.  It is very timely as I
have to reformat the code for inclusion into the GCC tree (which I plan
to do over the summer).  At the same time I'll convert the modules to
the above format one at a time.  I'll adapt the GNU coding style
standard (based from C) to include the above and produce a proposed GNU
coding style standard for M2,

regards,
Gaius


reply via email to

[Prev in Thread] Current Thread [Next in Thread]