Re: Open source? -> Need to read source to model?

[Jan Burse]

Dear Pietro

You wrote:

> Hi all,
> my opinion is that Swarm users have to know programming techniques,
> but it is not necessary that they read and understand Swarm source code.

This is an interesting question. I assume that you mean by Swarm source
code the code that is the base where everybody builds his models on. So
the Swarm source code has a similiar function like the Java JDK, namely
an application framework.

So the question is of more general interest, and has certainly already
generated a set of answers, particular from software engineering. To
my mind do come the following sketchy answers:

1) The documentation should contain the static structure (class diagrams)
2) The documentation should contain the dynamic behaviour (interaction diagrams)
3) Programmers program intelligible and use verbose comments
4) Real programmers don't document, the raw code is the documentation

In my opinion 1), 2), 3) and 4) are important. And an end-user should
have access to all of them. This is for example done in the Java JDK.
One can easily buy a book (e.g. Java in a Nutshell), look for 1) and 2).
Then one can install the Java JDK and freely browse the source, which
is 3) and 4) except for native methods.

Why are all levels important?

Now level 1) and 2) are important because frameworks today tend to be
object-oriented. Therefore one works from time to time by extending classes
or by using classes that come from some factories. So one has either to comply
with some contract or has to use some contract in his program. By contract
I mean the syntax and intended semantics of an interface. 1) and 2) should
elucidate that, and both are needed!

Finally level 3) and 4) are important because any verbal statement or diagram
from 1) and 2) is only an abstraction of what is really going on. So if you
would like to know what is really going, either because you need the details
in particular or because it helps you to produce your own abstract view of
the matter, then its really useful to have 3) and 4) available.

So the Java JDK did a good job, possibly it can be improved. I don't know
how good the open source of Netscapes Mozilla is. But I would apreciate
1), 2), 3) and 4) for Swarm and recommend it also to scientists. Its a car
and you should be allowed as much as possible to look under the hood.

Best Regards
--
Jan Burse                         Umweltphysik, EAWAG
Scheuchzerstr. 67                 Überlandstr. 133
8006 Zürich                       8600 Dübendorf
tel: +41-1-364 17 66              tel: +41-1-823 55 34




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