Index: src/Tuples/TupleExpansion.cc
===================================================================
--- src/Tuples/TupleExpansion.cc	(revision 77bfc801f3cb89b3b5dcb4ce8808bf2332aeef24)
+++ src/Tuples/TupleExpansion.cc	(revision 3f840e371860ab44fa91a1a4d720ef11582eb23e)
@@ -353,4 +353,9 @@
 	}
 
+	const ast::TypeInstType * isTtype( const ast::Type * type ) {
+		#warning unimplemented
+		return nullptr;
+	}
+
 	namespace {
 		/// determines if impurity (read: side-effects) may exist in a piece of code. Currently gives a very crude approximation, wherein any function call expression means the code may be impure