er case, k1 will be set to the current value of ak1, and will
not change when ak1 changes.
<p>
Parameters not yet defined have the value zero.
<p>
Example:
<pre>
gev = 100;
beam,energy=gev;
</pre>
the parameter on the left may appear on the right as well:
<pre>
x = x+1;
</pre>
Increases the value of x by 1. As a result, the SET statement of MAD-8
is no longer necessary and is not implemented.
<pre>
Circular definitions are allowed in the first form:
<pre>
a = b + 2;
b = a * b;
</pre>
However, circular defin