Raise error if values are incompatible

src/building_blocks.jl

@@ -241,6 +241,7 @@ apply_simple_constraint!(variable, ::Val{:min}) = @objective global_model() Min
 apply_simple_constraint!(variable, ::Val{:max}) = @objective global_model() Min objective_function(global_model()) - variable
 apply_simple_constraint!(variable, value::VariableType) = @constraint global_model() variable == value
 apply_simple_constraint!(variable::AbstractVector, value::AbstractVector) = [apply_simple_constraint!(v1, v2) for (v1, v2) in zip(variable, value)]
+apply_simple_constraint!(variable::Number, value::Number) = @assert variable ≈ value "Variable set to multiple incompatible values."
 
 
 """