Re: From extended Pascals to Ada 95 guide

[Gautier <gautier.demontmollin@maths.unine.ch>]

James Smith:

> Too bad the US gov didn't save some taxpayer dollars by just adopting Modula
> 2. Of course that would have made too much sense.

To save dollars they also could have adopted C...
With Modula-2, they should have spent perhaps more than Ada to make it usable...

The main problem with Modula-2 is that it keeps the rigid types
of "classic" Pascal. No problem for teaching or write a
"Pascal in Pascal" compiler, but for the real world you need
a flexible typing like "array(integer range <>) of..."

The second problem is the modularity: you have to open manually
the visibility for *all* identifiers you need! It made things
easier for writing a compiler, but it rapidily took longer to
write and maintain the "FROM...IMPORT..."s, with correct casing,
than to write your programs. Just extrapolate the "Hello World"
to have an idea...

MODULE PrintHelloWorld;

FROM InOut IMPORT WriteString, WriteLn;

BEGIN
        WriteString('Hello world!');
        WriteLn;
END PrintHelloWorld.

Another big problem was the library: there were vague recommendations
for text I/O, and iirc, nothing more. As a result, even "Hello World"
was non portable: some compilers wanted "WriteString('Hello world!');",
others wanted "WRITESTRING('Hello world!');" I let you guess what the
mess was with Math libraries...

Finally I doubt that the average US programmer would have been
patient enough to stand more than 5 minutes before Modula-2...
Already in Europe many keyboards were severely damaged!

______________________________________________________
Gautier  --  http://members.xoom.com/gdemont/gsoft.htm