Index: src/Tuples/TupleExpansion.cc
===================================================================
--- src/Tuples/TupleExpansion.cc	(revision 9b4f3290a76fc499cac978b84cc1ab000bd8d6d0)
+++ src/Tuples/TupleExpansion.cc	(revision 77bfc801f3cb89b3b5dcb4ce8808bf2332aeef24)
@@ -320,11 +320,13 @@
 	}
 	const ast::Type * makeTupleType( const std::vector<ast::ptr<ast::Expr>> & exprs ) {
-		assert(!"implemented; needs Type.cpp in build");
+		(void) exprs;
+		#warning Not implemented; needs Type.cpp in build
+		assertf(false, "Not implemented; needs Type.cpp in build");
 		// // produce the TupleType which aggregates the types of the exprs
 		// std::vector<ast::ptr<ast::Type>> types;
-		// ast::CV::Qualifiers quals{ 
-		// 	ast::CV::Const | ast::CV::Volatile | ast::CV::Restrict | ast::CV::Lvalue | 
+		// ast::CV::Qualifiers quals{
+		// 	ast::CV::Const | ast::CV::Volatile | ast::CV::Restrict | ast::CV::Lvalue |
 		// 	ast::CV::Atomic | ast::CV::Mutex };
-		
+
 		// for ( const ast::Expr * expr : exprs ) {
 		// 	assert( expr->result );
Index: src/Tuples/Tuples.h
===================================================================
--- src/Tuples/Tuples.h	(revision 9b4f3290a76fc499cac978b84cc1ab000bd8d6d0)
+++ src/Tuples/Tuples.h	(revision 77bfc801f3cb89b3b5dcb4ce8808bf2332aeef24)
@@ -29,7 +29,7 @@
 namespace Tuples {
 	// TupleAssignment.cc
-	void handleTupleAssignment( ResolvExpr::AlternativeFinder & currentFinder, UntypedExpr * assign, 
+	void handleTupleAssignment( ResolvExpr::AlternativeFinder & currentFinder, UntypedExpr * assign,
 		std::vector< ResolvExpr::AlternativeFinder >& args );
-	
+
 	// TupleExpansion.cc
 	/// expands z.[a, b.[x, y], c] into [z.a, z.b.x, z.b.y, z.c], inserting UniqueExprs as appropriate
@@ -48,4 +48,5 @@
 	/// returns a TypeInstType if `type` is a ttype, nullptr otherwise
 	TypeInstType * isTtype( Type * type );
+	const ast::TypeInstType * isTtype( const ast::Type * type );
 
 	/// returns true if the expression may contain side-effects.