<maction> to invoke Java Script functions

Hello,
I'm Bernardo and I worked in a project that deals with the publication
of mathematical exercises on the net.
At the moment these exercises, that may be solved on-line with the
support of the system, are displayed by using images
while answers are written by using textual expressions.
Now I'm going to change the representation of formulas by using MathML,
probably I will use Web Equation controls and/or Mathplayer plugin to
do my work (if someone may suggest other solution I thank him/her in
advance)
However before doing this changing I looked at MathML and I noticed that
probably there is somthing missing that I consider important. That is
why I'm writing you.
 
The structure of the MathML expressions let you to modify them using
other languages such as JavaScript, and moreover they may include
some action inside them by using <maction>. However often, at least in
the cases we used in our project, it is important to put the actions
that manipulate mathematical expression outside. That is because often
the actions are complex and may depend on information not contained in
the formulas. So according to me it will be very interesting to
introduce in the <maction> command also a way to invoke some extern
script functions.
As an example, imagine to have an equation and you can move the addends
by clicking them from the right side to the left one and viceversa, how
can you do this?
You my add to each addend the action that is invoked on the click and
then the extern function may manipulate the expression knowing which
part has been clicked.
Naturally the new expression, produced by the function, has to contain
adjusted <maction> instuctions in order to continue this process.
I believe that such kind of interactions MathML->Script Languages (and
not only Script Languages -> MathML) should be considered and
standardized.
 
If someone may suggest me alternative solutions or give me information
about these kind of problems I will appreciate very much, and I
apologize if the things I said may be not important or well known.
 
Thanks, 
     Bernardo
 
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        Ing. Bernardo D'Auria
 
        DIIMA - University of Salerno
        via Ponte don Melillo
        84084 Fisciano (SA)
        Italy
 
        tel.    +39 089 964264
        fax.    +39 089 964191
 
        e-mail  <mailto:dauria@diima.unisa.it> dauria@diima.unisa.it
 
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