diff --git a/Inferences/TheoryInstAndSimp.cpp b/Inferences/TheoryInstAndSimp.cpp
index 95644e057a..b4113803cc 100644
--- a/Inferences/TheoryInstAndSimp.cpp
+++ b/Inferences/TheoryInstAndSimp.cpp
@@ -246,7 +246,7 @@ Term* getFreshConstant(unsigned index, unsigned srt)
   Stack<Term*>* sortedConstants = constants[srt]; 
   while(index+1 > sortedConstants->length()){
     unsigned sym = env.signature->addFreshFunction(0,"$inst");
-    FunctionType* type = new FunctionType(srt);
+    OperatorType* type = OperatorType::getConstantsType(srt);
     env.signature->getFunction(sym)->setType(type);
     Term* fresh = Term::createConstant(sym);
     sortedConstants->push(fresh);
diff --git a/SAT/Z3Interfacing.cpp b/SAT/Z3Interfacing.cpp
index 55196882fc..74f33985f5 100644
--- a/SAT/Z3Interfacing.cpp
+++ b/SAT/Z3Interfacing.cpp
@@ -345,11 +345,11 @@ z3::expr Z3Interfacing::getz3expr(Term* trm,bool isLit,bool&nameExpression,bool
 
     Signature::Symbol* symb; 
     unsigned range_sort;
-    BaseType* type;
+    OperatorType* type;
     bool is_equality = false;
     if(isLit){
       symb = env.signature->getPredicate(trm->functor());
-      PredicateType* ptype = symb->predType();
+      OperatorType* ptype = symb->predType();
       type = ptype;
       range_sort = Sorts::SRT_BOOL;
       // check for equality
@@ -359,7 +359,7 @@ z3::expr Z3Interfacing::getz3expr(Term* trm,bool isLit,bool&nameExpression,bool
       }
     }else{
       symb = env.signature->getFunction(trm->functor());
-      FunctionType* ftype = symb->fnType(); 
+      OperatorType* ftype = symb->fnType();
       type = ftype;
       range_sort = ftype->result();
     }
@@ -434,16 +434,16 @@ z3::expr Z3Interfacing::getz3expr(Term* trm,bool isLit,bool&nameExpression,bool
       bool skip=false; 
       unsigned argsToPop=theory->getArity(interp);
 
-      if(theory->isStructuredSortInterpretation(interp)){
+      if(Theory::isPolymorphic(interp)){
         nameExpression = true;
-        switch(theory->convertToStructured(interp)){
-          case Theory::StructuredSortInterpretation::ARRAY_SELECT:
-          case Theory::StructuredSortInterpretation::ARRAY_BOOL_SELECT:
+        switch(interp){
+          case Theory::ARRAY_SELECT:
+          case Theory::ARRAY_BOOL_SELECT:
             // select(array,index)
             ret = select(args[0],args[1]);
             break;
 
-          case Theory::StructuredSortInterpretation::ARRAY_STORE:
+          case Theory::ARRAY_STORE:
             // store(array,index,value)
             ret = store(args[0],args[1],args[2]);
             break;