arbor-sim
Consider non-STATE range variables in ODE classification
When determining if a state evolution ODE system is of a particular form (for use in picking the solver implementation), modcc only looks at the dependence of the derivative formulae upon state variables.
A procedure, however, can also update range variables used in these formulae, and thereby potentially introduce a dependence on state variables that we do not examine.
Doing this correctly would be hard; the problem, at least in part, lies in the way NMODL is specified, and a solution might require an internal representation that is entirely functional. (Note that in the hh.mod implementation, for example, working variables such as minf are stored for each lane in the mechanism, when they should be represented as a form of local variable.)
