Advanced How-to Guide: Using Datum References

While it is not encouraged in the customary use of Mimi, some scenarios may make using references to datum desireable for code brevity and understandability.

Component References

Component references allow you to write cleaner model code when connecting components. The add_comp! function returns a reference to the component that you just added:

using Mimi

# create a component
@defcomp MyComp begin
    # empty

# construct a model and add the component
m = Model()
set_dimension!(m, :time, collect(2015:5:2110))
add_comp!(m, MyComp)
typeof(MyComp) # note the type is a Mimi Component Definition

If you want to get a reference to a component after the add_comp! call has been made, you can construct the reference as:

mycomponent = Mimi.ComponentReference(m, :MyComp)
typeof(mycomponent) # note the type is a Mimi Component Reference

You can use this component reference in place of the update_param! and connect_param! calls:

References in place of update_param!

The line update_param!(model, :MyComponent, :myparameter, myvalue) can be written as mycomponent[:myparameter] = myvalue, where mycomponent is a component reference.

References in place of connect_param!

The line connect_param!(model, :MyComponent, :myparameter, :YourComponent, :yourparameter) can be written as mycomponent[:myparameter] = yourcomponent[:yourparameter], where mycomponent and yourcomponent are component references.