Re: Ada versus Pascal

[Dennis Lee Bieber <wlfraed@ix.netcom.com>]

On Fri, 22 Oct 2021 17:29:26 -0700, Paul Rubin <no.email@nospam.invalid>
declaimed the following:

>Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:
>> 	Also, Pascal of the era typically did not support separate
>> compilation and/or include files -- programs were all single
>> monolithic files, any change required recompiling the entire program.
>
>I thought Ada was originally like that too.  The program could be split
>into multiple files, but they were expected to all be compiled together.

	No... Pretty much every build system for Ada focused on only rebuilding
the parts affected by a changed file -- by following WITH statements to
find required units (see the LRM for what a "unit" comprises) /and/
determining if that unit requires compilation. Timestamps or intermediate
files may be used in that determination. Changes in implementation (body)
require the body to be recompiled, but if the specification did not change,
then units WITHing the specification don't need to be compiled -- they just
need relinking with the updated body.

	GNAT's build system -- using the host OS filesystem as the "database"
-- required that separate files are generated for each unit. (cf: GNATCHOP)
All-in-One was the optional source file format accepted by some compilers
-- but other than the early language reference manuals, I haven't
encountered any text books that use that means of presenting code examples
(unless it is discussing the use of GNATCHOP itself <G>).

https://www.adahome.com/History/Stoneman/stoneman.htm
is the requirements document that DoD used to define the desired
environment around Ada development.
"""
4.E	APSE TOOLSET REQUIREMENTS
4.E.1	The tools in an APSE shall support the development of programs in
the Ada language as defined by the Ada reference manual. In particular an
APSE shall support the separate compilation features of the language.
"""
NOTE the last sentence


-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
	wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/