ENH: UniformList to wrap a single value into a list-like container

- refactor UniformField accordingly

applications/test/UniformField/Test-UniformField.C

@@ -1,15 +1,73 @@
-#include "UniformField.H"
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2020 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
+
+Application
+    Test-UniformField
+
+Description
+    Test uniform list/field
+\*---------------------------------------------------------------------------*/
+
+#include "argList.H"
 #include "vector.H"
 #include "IOstreams.H"
+#include "UniformField.H"
 
 using namespace Foam;
 
-int main()
+template<class T>
+void printInfo(const UniformList<T>& list, const label i=0)
 {
-    UniformField<scalar> uf1(13.1);
-    UniformField<vector> uf2(vector(1, 2, 3));
+    Info<< nl
+        << "value: " << list.value() << nl
+        << "cast:  " << static_cast<const T&>(list) << nl
+        << "[" << i << "] = " << list[i] << nl;
+}
 
-    Info<< "uf1 = " << uf1[22] << "; uf2 = " << uf2[1002] << endl;
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+//  Main program:
+
+int main(int argc, char *argv[])
+{
+    {
+        UniformField<scalar> fld(3.14159);
+
+        printInfo(fld, -100);
+
+        // Change value
+        fld.value() *= 0.5;
+
+        Info<< nl << "/= 2 " << nl;
+
+        printInfo(fld, -100);
+    }
+
+    {
+        UniformField<vector> fld(vector(1, 2, -1));
+
+        printInfo(fld);
+
+        // Change value
+        fld.value() *= 0.5;
+
+        Info<< nl << "/= 2 " << nl;
+
+        printInfo(fld);
+    }
+
+
+    Info<< "\nEnd\n" << endl;
 
     return 0;
 }
+
+// ************************************************************************* //