Re: [Axiom-developer] merge branches/daly to trunk

[Christian Aistleitner]

Hello,

> But Christian might be better in saying something why AxiomUnit does not  
> yet exist.

it is actually quite some time since I attempted to get AldorUnit to  
Axiom. As the crucial parts af the discussion happen orally between me and  
Ralf, parts of the arguments are lost.

The most important aspect is improving the Axiom experience--during the  
invostigation of Axiom, it turned out that the most important improvements  
AldorUnit provides cannot be brought to Axiom.
Having a full blown AxiomUnit, one would have tools to debug segfaults  
(although they do not seem to be an issue for Axiom) and other really bad  
behaving code. One should get really usable output from the Testing  
environment.
Ease of writing tests and its integration into Axiom is another important  
issue.

Aldor's TextWriter abilities where crucial for providing usable textual  
output. These possibilities are not present in Axiom -- but it seems  
Martin did some work in this direction.

For evaluating the possible benefits of AxiomUnit I played around with  
using the Aldor compiler for Axiom and loading the resulting code.  
Although I do not have the details at hand, I managed to crash Axiom badly  
without writing evil-looking Aldor code. Axiom behaved unexpectedly when  
loading functions compiled with Aldor. I remember race conditions when  
loading libraries. Recovery from errors proofed to be a serious issue. All  
in all, my experience of using the Aldor compiler with Axiom wasn't the  
best.
I do not want to spread FUD, it's just some time off. So the details faded  
a bit.

However, I will have a look at Martin's work. Maybe this will help in  
finally providing AxiomUnit.

Kind regards,
Christian