Change 'scalar constants' -> 'scalar constant expressions'

chapters/functions.tex

@@ -1984,7 +1984,7 @@ \section{External Function Interface}\label{external-function-interface}
 
 The {\lstinline[language=grammar]!external-function-call!} specification allows functions whose prototypes do not match the default assumptions as defined below to be called.  It also gives the name used to call the external function.  If the external call is not given explicitly, this name is assumed to be the same as the Modelica name.
 
-The only permissible kinds of expressions in the argument list are component references, scalar constants, and the function {\lstinline!size!} applied to an array and a constant dimension number.
+The only permissible kinds of expressions in the argument list are component references, scalar constant expressions, and the function {\lstinline!size!} applied to an array and a constant dimension number.
 The annotations are used to pass additional information to the compiler when necessary.
 
 A component reference to a component that is part of an input or output