diff --git a/src/parameter_indexing.jl b/src/parameter_indexing.jl
index d8b3122..79336a3 100644
--- a/src/parameter_indexing.jl
+++ b/src/parameter_indexing.jl
@@ -140,7 +140,7 @@ for (t1, t2) in [
     end
 end
 
-function _getp(sys, ::ArraySymbolic, ::NotSymbolic, p)
+function _getp(sys, ::ArraySymbolic, ::SymbolicTypeTrait, p)
     if is_parameter(sys, p)
         idx = parameter_index(sys, p)
         return invoke(_getp, Tuple{Any, NotSymbolic, NotSymbolic, Any},
@@ -218,7 +218,7 @@ for (t1, t2) in [
     end
 end
 
-function _setp(sys, ::ArraySymbolic, ::NotSymbolic, p)
+function _setp(sys, ::ArraySymbolic, ::SymbolicTypeTrait, p)
     if is_parameter(sys, p)
         idx = parameter_index(sys, p)
         return setp(sys, idx; run_hook = false)
diff --git a/src/state_indexing.jl b/src/state_indexing.jl
index 272c841..cd16b10 100644
--- a/src/state_indexing.jl
+++ b/src/state_indexing.jl
@@ -169,7 +169,7 @@ for (t1, t2) in [
     end
 end
 
-function _getu(sys, ::ArraySymbolic, ::NotSymbolic, sym)
+function _getu(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
         return getu(sys, idx)
@@ -233,7 +233,7 @@ for (t1, t2) in [
     end
 end
 
-function _setu(sys, ::ArraySymbolic, ::NotSymbolic, sym)
+function _setu(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
         if idx isa AbstractArray