Merge pull request #2765 from SciML/no_clocks

error for hybrid continuous/discrete systems

Author: ChrisRackauckas

src/systems/abstractsystem.jl

@@ -2320,6 +2320,13 @@ function Base.showerror(io::IO, e::ExtraEquationsSystemException)
     print(io, "ExtraEquationsSystemException: ", e.msg)
 end
 
+struct HybridSystemNotSupportedExcpetion <: Exception
+    msg::String
+end
+function Base.showerror(io::IO, e::HybridSystemNotSupportedExcpetion)
+    print(io, "HybridSystemNotSupportedExcpetion: ", e.msg)
+end
+
 function AbstractTrees.children(sys::ModelingToolkit.AbstractSystem)
     ModelingToolkit.get_systems(sys)
 end

src/systems/systemstructure.jl

@@ -635,6 +635,9 @@ function structural_simplify!(state::TearingState, io = nothing; simplify = fals
             check_consistency, fully_determined,
             kwargs...)
         if length(tss) > 1
+            if continuous_id > 0
+                throw(HybridSystemNotSupportedExcpetion("Hybrid continuous-discrete systems are currently not supported with the standard MTK compiler. This system requires JuliaSimCompiler.jl, see https://help.juliahub.com/juliasimcompiler/stable/"))
+            end
             # TODO: rename it to something else
             discrete_subsystems = Vector{ODESystem}(undef, length(tss))
             # Note that the appended_parameters must agree with