MATLAB: Optimization: solving ODE in objective function, how to pass solution to nonlinear constraint function

nonlinear constraintodeoptimization

Dear all,
More specifically, I have a model struct with all model parameters and a handle on the derivative function. I created "wrappers" that pass this struct in addition to the parameters for optimization to both the objective function and the constraint function:
    wrapper           = @(x) objfunc( x, model ) ;
    wrapperConstraint = @(x) constrfunc( x, model ) ;
    x0                = ...
    lb                = ...
    ub                = ...
    ... = fmincon( wrapper, x0, [], [], [], [], lb, ub, wrapperConstraint, ... ) ;
when the objective function is called, it solves a system of ODEs, but there is no direct way to pass it to the constraint function. The only two options that I see are
  1. Using a global variable for storing the solution.
  2. OOP: e.g. defining model not as a struct but as a handle class, and storing the solution in a property. This way both the objective function and the constraint function would access the same object.
Is there a better/cleaner option? What is the "correct/usual" way of doing this?
Thank you,
Karin
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