add extension for symbolic indexing of Num

Project.toml

@@ -1,6 +1,6 @@
 name = "GraphDynamics"
 uuid = "bcd5d0fe-e6b7-4ef1-9848-780c183c7f4c"
-version = "0.1.2"
+version = "0.1.3"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
@@ -15,11 +15,20 @@ SymbolicIndexingInterface = "2efcf032-c050-4f8e-a9bb-153293bab1f5"
 julia = "1.10"
 Accessors = "0.1"
 ConstructionBase = "1.5"
-OhMyThreads = "0.6"
+OhMyThreads = "0.6, 0.7"
 RecursiveArrayTools = "3"
 SciMLBase = "2"
 SparseArrays = "1"
 SymbolicIndexingInterface = "0.3"
+Symbolics = "6"
+ModelingToolkit = "9"
+
+[weakdeps]
+ModelingToolkit = "961ee093-0014-501f-94e3-6117800e7a78"
+Symbolics = "0c5d862f-8b57-4792-8d23-62f2024744c7"
+
+[extensions]
+MTKExt = ["Symbolics", "ModelingToolkit"]
 
 [extras]
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"

ext/MTKExt.jl

@@ -0,0 +1,28 @@
+module MTKExt
+
+using ModelingToolkit: ModelingToolkit, Num
+using Symbolics: Symbolics, tosymbol
+using GraphDynamics: GraphDynamics, GraphSystem
+using SymbolicIndexingInterface: SymbolicIndexingInterface
+
+function SymbolicIndexingInterface.is_variable(sys::GraphSystem, var::Num)
+    SymbolicIndexingInterface.is_variable(sys, tosymbol(var; escape=false))
+end
+
+function SymbolicIndexingInterface.variable_index(sys::GraphSystem, var::Num)
+    SymbolicIndexingInterface.variable_index(sys, tosymbol(var; escape=false))
+end
+
+function SymbolicIndexingInterface.is_parameter(sys::GraphSystem, var::Num)
+    SymbolicIndexingInterface.is_parameter(sys, tosymbol(var; escape=false))
+end
+
+function SymbolicIndexingInterface.parameter_index(sys::GraphSystem, var::Num)
+    SymbolicIndexingInterface.parameter_index(sys, tosymbol(var; escape=false))
+end
+
+function SymbolicIndexingInterface.is_independent_variable(sys::GraphSystem, sym::Num)
+    SymbolicIndexingInterface.is_independent_variable(sys, tosymbol(var; escape=false))
+end
+
+end