ENH: place more patch field attributes under template invariant Base

- attributes such as assignable(), coupled() etc

- common patchField types: calculatedType(), zeroGradientType() etc.
  This simplifies reference to these types without actually needing a
  typed patchField version.

ENH: add some basic patchField types to fieldTypes namespace

- allows more general use of the names

ENH: set extrapolated/calculated from patchInternalField directly

- avoids intermediate tmp

applications/solvers/compressible/rhoCentralFoam/BCs/T/smoluchowskiJumpTFvPatchScalarField.C

@@ -105,7 +105,8 @@ Foam::smoluchowskiJumpTFvPatchScalarField::smoluchowskiJumpTFvPatchScalarField
 
     if (!this->readValueEntry(dict))
     {
-        fvPatchField<scalar>::operator=(patchInternalField());
+        // Fallback: set to the internal field
+        fvPatchField<scalar>::patchInternalField(*this);
     }
 
     refValue() = *this;

applications/solvers/stressAnalysis/solidDisplacementFoam/tractionDisplacement/tractionDisplacementFvPatchVectorField.C

@@ -47,7 +47,7 @@ tractionDisplacementFvPatchVectorField
     traction_(p.size(), Zero),
     pressure_(p.size(), Zero)
 {
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
     gradient() = Zero;
 }
 
@@ -79,7 +79,7 @@ tractionDisplacementFvPatchVectorField
     traction_("traction", dict, p.size()),
     pressure_("pressure", dict, p.size())
 {
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
     gradient() = Zero;
 }
 

applications/solvers/stressAnalysis/solidEquilibriumDisplacementFoam/tractionDisplacementCorrection/tractionDisplacementCorrectionFvPatchVectorField.C

@@ -47,7 +47,7 @@ tractionDisplacementCorrectionFvPatchVectorField
     traction_(p.size(), Zero),
     pressure_(p.size(), Zero)
 {
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
     gradient() = Zero;
 }
 
@@ -79,7 +79,7 @@ tractionDisplacementCorrectionFvPatchVectorField
     traction_("traction", dict, p.size()),
     pressure_("pressure", dict, p.size())
 {
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
     gradient() = Zero;
 }
 

applications/test/pointField/Test-PointField.C

@@ -53,13 +53,13 @@ int main(int argc, char *argv[])
         (
             "U",
             runTime.timeName(),
-            mesh,
+            pMesh.thisDb(),
             IOobject::NO_READ,
-            IOobject::AUTO_WRITE
+            IOobject::NO_WRITE
         ),
         pMesh,
-        dimensionedVector(dimLength, Zero),
+        dimensionedVector(dimLength, Zero)
-        pointPatchVectorField::calculatedType()
+        // pointPatchFieldBase::calculatedType()
     );
 
     pointVectorField V(U + 2*U);

src/OpenFOAM/fields/Fields/fieldTypes.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2018 OpenCFD Ltd.
+    Copyright (C) 2018-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -42,4 +42,27 @@ const Foam::wordList Foam::fieldTypes::basic
 });
 
 
+// Commonly used patch field types
+
+const Foam::word Foam::fieldTypes::emptyType
+(
+    Foam::fieldTypes::emptyTypeName_()
+);
+
+const Foam::word Foam::fieldTypes::calculatedType
+(
+    Foam::fieldTypes::calculatedTypeName_()
+);
+
+const Foam::word Foam::fieldTypes::extrapolatedCalculatedType
+(
+    Foam::fieldTypes::extrapolatedCalculatedTypeName_()
+);
+
+const Foam::word Foam::fieldTypes::zeroGradientType
+(
+    Foam::fieldTypes::zeroGradientTypeName_()
+);
+
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

src/OpenFOAM/fields/Fields/fieldTypes.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2018 OpenCFD Ltd.
+    Copyright (C) 2018-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -24,8 +24,15 @@ License
     You should have received a copy of the GNU General Public License
     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
+Namespace
+    Foam::fieldTypes
+
 Description
-    Header files for all the primitive types that Fields are instantiated for.
+    Collection of common field types
+
+Note
+    The fieldTypes header contains macros for primitive types
+    that Fields are instantiated for.
 
 \*---------------------------------------------------------------------------*/
 
@@ -69,9 +76,40 @@ namespace Foam
 {
 namespace fieldTypes
 {
-    //- Standard basic field types (label, scalar, vector, tensor, etc)
+
-    //  These also correspond to cloud output fields.
+//- Standard basic field types (label, scalar, vector, tensor, etc)
-    extern const wordList basic;
+//  These also correspond to cloud output fields.
+extern const wordList basic;
+
+
+// Commonly used patch field types
+
+//- An \c empty patch field type
+inline const char* emptyTypeName_() noexcept { return "empty"; }
+
+//- An \c empty patch field type
+extern const word emptyType;
+
+//- A \c calculated patch field type
+inline const char* calculatedTypeName_() noexcept { return "calculated"; }
+
+//- A \c calculated patch field type
+extern const word calculatedType;
+
+//- A combined \c zero-gradient and \c calculated patch field type
+inline const char* extrapolatedCalculatedTypeName_() noexcept
+{
+    return "extrapolatedCalculated";
+}
+
+//- A combined \c zero-gradient and \c calculated patch field type
+extern const word extrapolatedCalculatedType;
+
+//- A \c zeroGradient patch field type
+inline const char* zeroGradientTypeName_() noexcept { return "zeroGradient"; }
+
+//- A \c zeroGradient patch field type
+extern const word zeroGradientType;
 
 } // End namespace fieldTypes
 } // End namespace Foam

src/OpenFOAM/fields/pointPatchFields/basic/calculated/calculatedPointPatchField.C

@@ -28,15 +28,6 @@ License
 
 #include "calculatedPointPatchField.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::pointPatchField<Type>::calculatedType()
-{
-    return Foam::calculatedPointPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>

src/OpenFOAM/fields/pointPatchFields/basic/calculated/calculatedPointPatchField.H

@@ -53,11 +53,10 @@ class calculatedPointPatchField
 :
     public pointPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName("calculated");
+    TypeName("calculated");  // fieldTypes::calculatedTypeName_()
 
 
     // Constructors

src/OpenFOAM/fields/pointPatchFields/basic/fixedValue/fixedValuePointPatchField.H

@@ -139,18 +139,13 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
-    // Member operators
+    // Member Operators
 
         // Disable assignment operators
 

src/OpenFOAM/fields/pointPatchFields/basic/zeroGradient/zeroGradientPointPatchField.C

@@ -27,15 +27,6 @@ License
 
 #include "zeroGradientPointPatchField.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::pointPatchField<Type>::zeroGradientType()
-{
-    return Foam::zeroGradientPointPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>

src/OpenFOAM/fields/pointPatchFields/basic/zeroGradient/zeroGradientPointPatchField.H

@@ -56,7 +56,7 @@ class zeroGradientPointPatchField
 public:
 
     //- Runtime type information
-    TypeName("zeroGradient");
+    TypeName("zeroGradient");  // fieldTypes::zeroGradientTypeName_()
 
 
     // Constructors

src/OpenFOAM/fields/pointPatchFields/constraint/empty/emptyPointPatchField.H

@@ -34,8 +34,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef emptyPointPatchField_H
+#ifndef Foam_emptyPointPatchField_H
-#define emptyPointPatchField_H
+#define Foam_emptyPointPatchField_H
 
 #include "pointPatchField.H"
 #include "emptyPointPatch.H"
@@ -54,11 +54,10 @@ class emptyPointPatchField
 :
     public pointPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName(emptyPointPatch::typeName_());
+    TypeName(emptyPointPatch::typeName_());  // fieldTypes::emptyTypeName_()
 
 
     // Constructors

src/OpenFOAM/fields/pointPatchFields/pointPatchField/pointPatchField.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -140,8 +140,50 @@ public:
     virtual ~pointPatchFieldBase() = default;
 
 
+    // Static Member Functions
+
+        //- The type name for \c empty patch fields
+        static const word& emptyType() noexcept
+        {
+            return Foam::fieldTypes::emptyType;
+        }
+
+        //- The type name for \c calculated patch fields
+        static const word& calculatedType() noexcept
+        {
+            return Foam::fieldTypes::calculatedType;
+        }
+
+        //- The type name for \c zeroGradient patch fields
+        static const word& zeroGradientType() noexcept
+        {
+            return Foam::fieldTypes::zeroGradientType;
+        }
+
+
     // Member Functions
 
+    // Attributes
+
+        //- True if the patch field fixes a value
+        virtual bool fixesValue() const
+        {
+            return false;
+        }
+
+        //- True if the patch field is coupled
+        virtual bool coupled() const
+        {
+            return false;
+        }
+
+        //- The constraint type the pointPatchField implements
+        virtual const word& constraintType() const
+        {
+            return word::null;
+        }
+
+
     // Access
 
         //- The associated objectRegistry
@@ -366,34 +408,6 @@ public:
 
     // Member Functions
 
-        //- The type name for calculated patch fields
-        static const word& calculatedType();
-
-        //- The type name for zeroGradient patch fields
-        static const word& zeroGradientType();
-
-
-    // Attributes
-
-        //- True if this patch field fixes a value
-        virtual bool fixesValue() const
-        {
-            return false;
-        }
-
-        //- True if this patch field is coupled
-        virtual bool coupled() const
-        {
-            return false;
-        }
-
-        //- The constraint type this pointPatchField implements.
-        virtual const word& constraintType() const
-        {
-            return word::null;
-        }
-
-
     // Access
 
         //- Return the patch size

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/fixedShearStress/fixedShearStressFvPatchVectorField.C

@@ -56,7 +56,7 @@ Foam::fixedShearStressFvPatchVectorField::fixedShearStressFvPatchVectorField
     fixedValueFvPatchVectorField(p, iF, dict, IOobjectOption::NO_READ),
     tau0_(dict.getOrDefault<vector>("tau", Zero))
 {
-    fvPatchField<vector>::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
 }
 
 

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/epsilonWallFunctions/epsilonWallFunction/epsilonWallFunctionFvPatchScalarField.C

@@ -366,7 +366,7 @@ epsilonWallFunctionFvPatchScalarField
     cornerWeights_()
 {
     // Apply zero-gradient condition on start-up
-    this->operator==(patchInternalField());
+    fvPatchField<scalar>::patchInternalField(*this);
 }
 
 

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/omegaWallFunctions/omegaWallFunction/omegaWallFunctionFvPatchScalarField.C

@@ -359,7 +359,7 @@ Foam::omegaWallFunctionFvPatchScalarField::omegaWallFunctionFvPatchScalarField
     cornerWeights_()
 {
     // apply zero-gradient condition on start-up
-    this->operator==(patchInternalField());
+    fvPatchField<scalar>::patchInternalField(*this);
 }
 
 

src/atmosphericModels/derivedFvPatchFields/atmTurbulentHeatFluxTemperature/atmTurbulentHeatFluxTemperatureFvPatchScalarField.C

@@ -114,8 +114,8 @@ atmTurbulentHeatFluxTemperatureFvPatchScalarField
     }
     else
     {
-        fvPatchField<scalar>::operator=(patchInternalField());
+        fvPatchField<scalar>::patchInternalField(*this);
-        gradient() = 0.0;
+        gradient() = Zero;
     }
 }
 

src/dynamicFaMesh/interfaceTrackingFvMesh/fvPatchFields/freeSurfaceVelocity/freeSurfaceVelocityFvPatchVectorField.C

@@ -70,7 +70,7 @@ freeSurfaceVelocityFvPatchVectorField
     fixedGradientFvPatchVectorField(p, iF)
 {
     fvPatchFieldBase::readDict(dict);
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
 }
 
 

src/finiteArea/fields/faPatchFields/basic/calculated/calculatedFaPatchField.C

@@ -29,15 +29,6 @@ License
 #include "calculatedFaPatchField.H"
 #include "faPatchFieldMapper.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::faPatchField<Type>::calculatedType()
-{
-    return Foam::calculatedFaPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class Type>

src/finiteArea/fields/faPatchFields/basic/calculated/calculatedFaPatchField.H

@@ -60,7 +60,7 @@ class calculatedFaPatchField
 public:
 
     //- Runtime type information
-    TypeName("calculated");
+    TypeName("calculated");  // fieldTypes::calculatedTypeName_()
 
 
     // Constructors
@@ -126,17 +126,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteArea/fields/faPatchFields/basic/extrapolatedCalculated/extrapolatedCalculatedFaPatchField.C

@@ -54,7 +54,8 @@ extrapolatedCalculatedFaPatchField
 :
     calculatedFaPatchField<Type>(p, iF, dict, IOobjectOption::NO_READ)
 {
-    calculatedFaPatchField<Type>::operator==(this->patchInternalField());
+    // Set to the internal field
+    faPatchField<Type>::patchInternalField(*this);
 }
 
 

src/finiteArea/fields/faPatchFields/basic/extrapolatedCalculated/extrapolatedCalculatedFaPatchField.H

@@ -73,6 +73,7 @@ public:
 
     //- Runtime type information
     TypeName("extrapolatedCalculated");
+    // fieldTypes::extrapolatedCalculatedTypeName_()
 
 
     // Constructors

src/finiteArea/fields/faPatchFields/basic/fixedValue/fixedValueFaPatchField.H

@@ -127,17 +127,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteArea/fields/faPatchFields/basic/mixed/mixedFaPatchField.H

@@ -164,17 +164,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: the patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Return defining fields

src/finiteArea/fields/faPatchFields/basic/sliced/slicedFaPatchField.H

@@ -139,12 +139,10 @@ public:
 
     // Member Functions
 
-    // Attributes
-
         //- True: this patch field fixes a value.
         virtual bool fixesValue() const { return true; }
 
-        //- False: this patch field is not altered by assignment
+        //- False: this patch field is not altered by assignment.
         virtual bool assignable() const { return false; }
 
 

src/finiteArea/fields/faPatchFields/basic/zeroGradient/zeroGradientFaPatchField.C

@@ -28,15 +28,6 @@ License
 #include "zeroGradientFaPatchField.H"
 #include "faPatchFieldMapper.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::faPatchField<Type>::zeroGradientType()
-{
-    return Foam::zeroGradientFaPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>
@@ -109,7 +100,8 @@ void Foam::zeroGradientFaPatchField<Type>::evaluate(const Pstream::commsTypes)
         this->updateCoeffs();
     }
 
-    this->operator==(this->patchInternalField());
+    // Set to the internal field
+    faPatchField<Type>::patchInternalField(*this);
     faPatchField<Type>::evaluate();
 }
 

src/finiteArea/fields/faPatchFields/basic/zeroGradient/zeroGradientFaPatchField.H

@@ -38,8 +38,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef zeroGradientFaPatchField_H
+#ifndef Foam_zeroGradientFaPatchField_H
-#define zeroGradientFaPatchField_H
+#define Foam_zeroGradientFaPatchField_H
 
 #include "faPatchField.H"
 
@@ -60,7 +60,7 @@ class zeroGradientFaPatchField
 public:
 
     //- Runtime type information
-    TypeName("zeroGradient");
+    TypeName("zeroGradient");  // fieldTypes::zeroGradientTypeName_()
 
 
     // Constructors
@@ -132,16 +132,14 @@ public:
             //- Return gradient at boundary
             virtual tmp<Field<Type>> snGrad() const
             {
-                return tmp<Field<Type>>
+                return tmp<Field<Type>>::New(this->size(), Zero);
-                (
-                    new Field<Type>(this->size(), Zero)
-                );
             }
 
             //- Evaluate the patch field
             virtual void evaluate
             (
-                const Pstream::commsTypes commsType = Pstream::commsTypes::blocking
+                const Pstream::commsTypes commsType =
+                    Pstream::commsTypes::blocking
             );
 
             //- Return the matrix diagonal coefficients corresponding to the

src/finiteArea/fields/faPatchFields/derived/clampedPlate/clampedPlateFaPatchField.C

@@ -58,7 +58,8 @@ clampedPlateFaPatchField<Type>::clampedPlateFaPatchField
 :
     faPatchField<Type>(p, iF, dict, IOobjectOption::NO_READ)
 {
-    faPatchField<Type>::operator=(this->patchInternalField());
+    // Set to the internal field
+    faPatchField<Type>::patchInternalField(*this);
 }
 
 

src/finiteArea/fields/faPatchFields/derived/fixedValueOutflow/fixedValueOutflowFaPatchField.H

@@ -125,17 +125,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: the patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteArea/fields/faPatchFields/faPatchField/faPatchField.H

@@ -145,8 +145,53 @@ public:
     virtual ~faPatchFieldBase() = default;
 
 
+    // Static Member Functions
+
+        //- The type name for \c empty patch fields
+        static const word& emptyType() noexcept
+        {
+            return Foam::fieldTypes::emptyType;
+        }
+
+        //- The type name for \c calculated patch fields
+        static const word& calculatedType() noexcept
+        {
+            return Foam::fieldTypes::calculatedType;
+        }
+
+        //- The type name for \c extrapolatedCalculated patch fields
+        //- combines \c zero-gradient and \c calculated
+        static const word& extrapolatedCalculatedType() noexcept
+        {
+            return Foam::fieldTypes::extrapolatedCalculatedType;
+        }
+
+        //- The type name for \c zeroGradient patch fields
+        static const word& zeroGradientType() noexcept
+        {
+            return Foam::fieldTypes::zeroGradientType;
+        }
+
+
     // Member Functions
 
+    // Attributes
+
+        //- True if the patch field fixes a value.
+        //  Needed to check if a level has to be specified while solving
+        //  Poissons equations.
+        virtual bool fixesValue() const
+        {
+            return false;
+        }
+
+        //- True if the patch field is coupled
+        virtual bool coupled() const
+        {
+            return false;
+        }
+
+
     // Access
 
         //- The associated objectRegistry
@@ -411,30 +456,6 @@ public:
 
     // Member Functions
 
-        //- The type name for calculated patch fields
-        static const word& calculatedType();
-
-        //- The type name for zeroGradient patch fields
-        static const word& zeroGradientType();
-
-
-    // Attributes
-
-        //- True if this patch field fixes a value.
-        //  Needed to check if a level has to be specified while solving
-        //  Poissons equations.
-        virtual bool fixesValue() const
-        {
-            return false;
-        }
-
-        //- True if this patch field is coupled
-        virtual bool coupled() const
-        {
-            return false;
-        }
-
-
     // Access
 
         //- Return const-reference to the dimensioned internal field

src/finiteArea/fields/faePatchFields/basic/calculated/calculatedFaePatchField.C

@@ -29,15 +29,6 @@ License
 #include "calculatedFaePatchField.H"
 #include "faPatchFieldMapper.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::faePatchField<Type>::calculatedType()
-{
-    return Foam::calculatedFaePatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>

src/finiteArea/fields/faePatchFields/basic/calculated/calculatedFaePatchField.H

@@ -60,7 +60,7 @@ class calculatedFaePatchField
 public:
 
     //- Runtime type information
-    TypeName("calculated");
+    TypeName("calculated");  // fieldTypes::calculatedTypeName_()
 
 
     // Constructors
@@ -128,16 +128,11 @@ public:
 
     // Member Functions
 
-        // Access
+        //- True: the patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
+    // Other
 
         //- Write
         virtual void write(Ostream&) const;

src/finiteArea/fields/faePatchFields/basic/fixedValue/fixedValueFaePatchField.H

@@ -130,24 +130,19 @@ public:
     virtual ~fixedValueFaePatchField() = default;
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
+    // Other
 
         //- Write
         virtual void write(Ostream&) const;
 
 
-    // Member operators
+    // Member Operators
 
         virtual void operator=(const UList<Type>&) {}
 

src/finiteArea/fields/faePatchFields/basic/sliced/slicedFaePatchField.H

@@ -132,8 +132,6 @@ public:
 
     // Member Functions
 
-    // Attributes
-
         //- True: this patch field fixes a value.
         virtual bool fixesValue() const { return true; }
 

src/finiteArea/fields/faePatchFields/constraint/empty/emptyFaePatchField.H

@@ -61,7 +61,7 @@ class emptyFaePatchField
 public:
 
     //- Runtime type information
-    TypeName("empty");
+    TypeName(emptyFaPatch::typeName_());  // fieldTypes::emptyTypeName_()
 
 
     // Constructors

src/finiteArea/fields/faePatchFields/faePatchField/faePatchField.H

@@ -131,8 +131,40 @@ public:
     virtual ~faePatchFieldBase() = default;
 
 
+    // Static Member Functions
+
+        //- The type name for \c empty patch fields
+        static const word& emptyType() noexcept
+        {
+            return Foam::fieldTypes::emptyType;
+        }
+
+        //- The type name for \c calculated patch fields
+        static const word& calculatedType() noexcept
+        {
+            return Foam::fieldTypes::calculatedType;
+        }
+
+
     // Member Functions
 
+    // Attributes
+
+        //- True if the patch field fixes a value.
+        //  Needed to check if a level has to be specified while solving
+        //  Poissons equations.
+        virtual bool fixesValue() const
+        {
+            return false;
+        }
+
+        //- True if the patch field is coupled
+        virtual bool coupled() const
+        {
+            return false;
+        }
+
+
     // Access
 
         //- The associated objectRegistry
@@ -390,27 +422,6 @@ public:
 
     // Member Functions
 
-        //- The type name for calculated patch fields
-        static const word& calculatedType();
-
-
-    // Attributes
-
-        //- True if this patch field fixes a value.
-        //  Needed to check if a level has to be specified while solving
-        //  Poissons equations.
-        virtual bool fixesValue() const
-        {
-            return false;
-        }
-
-        //- True if this patch field is coupled
-        virtual bool coupled() const
-        {
-            return false;
-        }
-
-
     // Access
 
         //- Return const-reference to the dimensioned internal field

src/finiteVolume/fields/fvPatchFields/basic/calculated/calculatedFvPatchField.C

@@ -29,15 +29,6 @@ License
 #include "calculatedFvPatchField.H"
 #include "fvPatchFieldMapper.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::fvPatchField<Type>::calculatedType()
-{
-    return Foam::calculatedFvPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class Type>

src/finiteVolume/fields/fvPatchFields/basic/calculated/calculatedFvPatchField.H

@@ -69,11 +69,10 @@ class calculatedFvPatchField
 :
     public fvPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName("calculated");
+    TypeName("calculated");  // fieldTypes::calculatedTypeName_()
 
 
     // Constructors
@@ -154,17 +153,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteVolume/fields/fvPatchFields/basic/directionMixed/directionMixedFvPatchField.H

@@ -130,23 +130,13 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true: this patch field fixes a value.
+        //- False: this patch field is not altered by assignment.
-            //  Needed to check if a level has to be specified while solving
+        virtual bool assignable() const { return false; }
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
-
-            //- Return false: this patch field is not altered by assignment
-            virtual bool assignable() const
-            {
-                return false;
-            }
 
 
         // Mapping functions

src/finiteVolume/fields/fvPatchFields/basic/extrapolatedCalculated/extrapolatedCalculatedFvPatchField.C

@@ -54,7 +54,8 @@ extrapolatedCalculatedFvPatchField
 :
     calculatedFvPatchField<Type>(p, iF, dict, IOobjectOption::NO_READ)
 {
-    calculatedFvPatchField<Type>::operator==(this->patchInternalField());
+    // Set to the internal field
+    fvPatchField<Type>::patchInternalField(*this);
 }
 
 
@@ -108,7 +109,8 @@ void Foam::extrapolatedCalculatedFvPatchField<Type>::evaluate
         this->updateCoeffs();
     }
 
-    calculatedFvPatchField<Type>::operator==(this->patchInternalField());
+    // Set to the internal field
+    fvPatchField<Type>::patchInternalField(*this);
     calculatedFvPatchField<Type>::evaluate();
 }
 

src/finiteVolume/fields/fvPatchFields/basic/extrapolatedCalculated/extrapolatedCalculatedFvPatchField.H

@@ -72,6 +72,7 @@ public:
 
     //- Runtime type information
     TypeName("extrapolatedCalculated");
+    // fieldTypes::extrapolatedCalculatedTypeName_()
 
 
     // Constructors

src/finiteVolume/fields/fvPatchFields/basic/fixedValue/fixedValueFvPatchField.H

@@ -166,23 +166,13 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true if this patch field fixes a value.
+        //- False: this patch field is not altered by assignment.
-            //  Needed to check if a level has to be specified while solving
+        virtual bool assignable() const { return false; }
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
-
-            //- Return false: this patch field is not altered by assignment
-            virtual bool assignable() const
-            {
-                return false;
-            }
 
 
         // Evaluation functions

src/finiteVolume/fields/fvPatchFields/basic/mixed/mixedFvPatchField.H

@@ -188,23 +188,13 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true if this patch field fixes a value.
+        //- False: this patch field is not altered by assignment.
-            //  Needed to check if a level has to be specified while solving
+        virtual bool assignable() const { return false; }
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
-
-            //- Return false: this patch field is not altered by assignment
-            virtual bool assignable() const
-            {
-                return false;
-            }
 
 
         // Return defining fields

src/finiteVolume/fields/fvPatchFields/basic/sliced/slicedFvPatchField.H

@@ -136,23 +136,13 @@ public:
     virtual ~slicedFvPatchField<Type>();
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field fixes a value.
+        virtual bool fixesValue() const { return true; }
 
-            //- Return true if this patch field fixes a value.
+        //- False: this patch field is not altered by assignment.
-            //  Needed to check if a level has to be specified while solving
+        virtual bool assignable() const { return false; }
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
-
-            //- Return false: this patch field is not altered by assignment
-            virtual bool assignable() const
-            {
-                return false;
-            }
 
 
         // Evaluation functions

src/finiteVolume/fields/fvPatchFields/basic/transform/transformFvPatchField.H

@@ -113,16 +113,10 @@ public:
         ) const = 0;
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment.
-
+        virtual bool assignable() const { return true; }
-            //- Return true if the value of the patch field
-            //  is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteVolume/fields/fvPatchFields/basic/zeroGradient/zeroGradientFvPatchField.C

@@ -28,16 +28,6 @@ License
 #include "zeroGradientFvPatchField.H"
 #include "fvPatchFieldMapper.H"
 
-
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::fvPatchField<Type>::zeroGradientType()
-{
-    return zeroGradientFvPatchField<Type>::typeName;
-}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>
@@ -61,7 +51,8 @@ Foam::zeroGradientFvPatchField<Type>::zeroGradientFvPatchField
 :
     fvPatchField<Type>(p, iF, dict, IOobjectOption::NO_READ)
 {
-    fvPatchField<Type>::operator=(this->patchInternalField());
+    // Set to the internal field
+    fvPatchField<Type>::patchInternalField(*this);
 }
 
 
@@ -109,7 +100,8 @@ void Foam::zeroGradientFvPatchField<Type>::evaluate(const Pstream::commsTypes)
         this->updateCoeffs();
     }
 
-    fvPatchField<Type>::operator==(this->patchInternalField());
+    // Set to the internal field
+    fvPatchField<Type>::patchInternalField(*this);
     fvPatchField<Type>::evaluate();
 }
 

src/finiteVolume/fields/fvPatchFields/basic/zeroGradient/zeroGradientFvPatchField.H

@@ -47,8 +47,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef zeroGradientFvPatchField_H
+#ifndef Foam_zeroGradientFvPatchField_H
-#define zeroGradientFvPatchField_H
+#define Foam_zeroGradientFvPatchField_H
 
 #include "fvPatchField.H"
 
@@ -66,11 +66,10 @@ class zeroGradientFvPatchField
 :
     public fvPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName("zeroGradient");
+    TypeName("zeroGradient");  // fieldTypes::zeroGradientTypeName_()
 
 
     // Constructors
@@ -142,10 +141,7 @@ public:
             //- Return gradient at boundary
             virtual tmp<Field<Type>> snGrad() const
             {
-                return tmp<Field<Type>>
+                return tmp<Field<Type>>::New(this->size(), Zero);
-                (
-                    new Field<Type>(this->size(), Zero)
-                );
             }
 
             //- Evaluate the patch field

src/finiteVolume/fields/fvPatchFields/constraint/cyclicAMI/cyclicAMIFvPatchField.C

@@ -77,7 +77,7 @@ Foam::cyclicAMIFvPatchField<Type>::cyclicAMIFvPatchField
         }
         else
         {
-            fvPatchField<Type>::operator=(this->patchInternalField());
+            fvPatchField<Type>::patchInternalField(*this);
         }
     }
 }

src/finiteVolume/fields/fvPatchFields/constraint/empty/emptyFvPatchField.H

@@ -49,8 +49,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef emptyFvPatchField_H
+#ifndef Foam_emptyFvPatchField_H
-#define emptyFvPatchField_H
+#define Foam_emptyFvPatchField_H
 
 #include "fvPatchField.H"
 #include "emptyFvPatch.H"
@@ -69,11 +69,10 @@ class emptyFvPatchField
 :
     public fvPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName(emptyFvPatch::typeName_());
+    TypeName(emptyFvPatch::typeName_());  // fieldTypes::emptyTypeName_()
 
 
     // Constructors

src/finiteVolume/fields/fvPatchFields/constraint/processor/processorFvPatchField.C

@@ -89,7 +89,7 @@ Foam::processorFvPatchField<Type>::processorFvPatchField
     // Use 'value' supplied, or set to internal field
     if (!this->readValueEntry(dict))
     {
-        fvPatchField<Type>::operator=(this->patchInternalField());
+        fvPatchField<Type>::patchInternalField(*this);
     }
 }
 

src/finiteVolume/fields/fvPatchFields/derived/advective/advectiveFvPatchField.C

@@ -91,7 +91,7 @@ Foam::advectiveFvPatchField<Type>::advectiveFvPatchField
     // Use 'value' supplied, or set to internal field
     if (!this->readValueEntry(dict))
     {
-        fvPatchField<Type>::operator=(this->patchInternalField());
+        fvPatchField<Type>::patchInternalField(*this);
     }
 
     this->refValue() = *this;

src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchField.C

@@ -189,7 +189,7 @@ Foam::codedFixedValueFvPatchField<Type>::codedFixedValueFvPatchField
     if (!this->readValueEntry(dict))
     {
         // Assign dummy value to get redirectPatchField not fail
-        this->operator==(this->patchInternalField());
+        fvPatchField<Type>::patchInternalField(*this);
 
         this->evaluate(Pstream::commsTypes::blocking);
     }

src/finiteVolume/fields/fvPatchFields/derived/electrostaticDeposition/electrostaticDepositionFvPatchScalarField.C

@@ -208,7 +208,7 @@ electrostaticDepositionFvPatchScalarField
 {
     if (!this->readValueEntry(dict))
     {
-        fvPatchScalarField::operator=(patchInternalField());
+        fvPatchField<scalar>::patchInternalField(*this);
     }
 
     // If flow is multiphase

src/finiteVolume/fields/fvPatchFields/derived/fixedFluxPressure/fixedFluxPressureFvPatchScalarField.C

@@ -65,7 +65,7 @@ Foam::fixedFluxPressureFvPatchScalarField::fixedFluxPressureFvPatchScalarField
     }
     else
     {
-        fvPatchField<scalar>::operator=(patchInternalField());
+        fvPatchField<scalar>::patchInternalField(*this);
         gradient() = Zero;
     }
 }

src/finiteVolume/fields/fvPatchFields/derived/fixedNormalInletOutletVelocity/fixedNormalInletOutletVelocityFvPatchVectorField.H

@@ -188,15 +188,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment.
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/fixedNormalSlip/fixedNormalSlipFvPatchField.H

@@ -178,13 +178,11 @@ public:
 
     // Member Functions
 
-        // Access
+        //- False: this patch field is not altered by assignment.
+        virtual bool assignable() const { return false; }
 
-            //- This patch field is not altered by assignment
+
-            virtual bool assignable() const
+        // Access
-            {
-                return false;
-            }
 
             //- User-defined input field (modifiable field)
             virtual Field<Type>& fixedValue()

src/finiteVolume/fields/fvPatchFields/derived/fluxCorrectedVelocity/fluxCorrectedVelocityFvPatchVectorField.C

@@ -75,7 +75,7 @@ fluxCorrectedVelocityFvPatchVectorField
     rhoName_(dict.getOrDefault<word>("rho", "rho"))
 {
     fvPatchFieldBase::readDict(dict);
-    fvPatchVectorField::operator=(patchInternalField());
+    fvPatchField<vector>::patchInternalField(*this);
 }
 
 

src/finiteVolume/fields/fvPatchFields/derived/inletOutlet/inletOutletFvPatchField.H

@@ -166,13 +166,8 @@ public:
 
     // Member functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment.
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         //- Update the coefficients associated with the patch field

src/finiteVolume/fields/fvPatchFields/derived/outletMappedUniformInlet/outletMappedUniformInletFvPatchField.C

@@ -170,7 +170,8 @@ outletMappedUniformInletFvPatchField
 
     if (!this->readValueEntry(dict))
     {
-        fvPatchField<Type>::operator=(this->patchInternalField());
+        // Fallback: set to the internal field
+        fvPatchField<Type>::patchInternalField(*this);
     }
 }
 
@@ -203,7 +204,8 @@ outletMappedUniformInletFvPatchField
     }
     else
     {
-        fvPatchField<Type>::operator=(this->patchInternalField());
+        // Fallback: set to the internal field
+        fvPatchField<Type>::patchInternalField(*this);
     }
 }
 

src/finiteVolume/fields/fvPatchFields/derived/outletPhaseMeanVelocity/outletPhaseMeanVelocityFvPatchVectorField.C

@@ -86,7 +86,7 @@ Foam::outletPhaseMeanVelocityFvPatchVectorField
 
     if (!this->readValueEntry(dict))
     {
-        fvPatchVectorField::operator=(patchInternalField());
+        fvPatchField<vector>::patchInternalField(*this);
     }
 }
 

src/finiteVolume/fields/fvPatchFields/derived/partialSlip/partialSlipFvPatchField.H

@@ -166,13 +166,10 @@ public:
 
     // Member Functions
 
-        // Access/attributes
+        //- False: this patch field is not altered by assignment
+        virtual bool assignable() const { return false; }
 
-            //- This patch field is not altered by assignment
+        // Access
-            virtual bool assignable() const
-            {
-                return false;
-            }
 
             virtual Field<Type>& refValue()
             {

src/finiteVolume/fields/fvPatchFields/derived/phaseHydrostaticPressure/phaseHydrostaticPressureFvPatchScalarField.H

@@ -184,15 +184,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressureDirectedInletOutletVelocity/pressureDirectedInletOutletVelocityFvPatchVectorField.H

@@ -176,15 +176,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressureDirectedInletVelocity/pressureDirectedInletVelocityFvPatchVectorField.H

@@ -172,15 +172,11 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
+        virtual bool assignable() const { return true; }
 
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
         // Access
 

src/finiteVolume/fields/fvPatchFields/derived/pressureInletOutletParSlipVelocity/pressureInletOutletParSlipVelocityFvPatchVectorField.H

@@ -172,15 +172,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressureInletOutletVelocity/pressureInletOutletVelocityFvPatchVectorField.H

@@ -162,15 +162,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressureInletUniformVelocity/pressureInletUniformVelocityFvPatchVectorField.H

@@ -137,15 +137,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         //- Update the coefficients associated with the patch field

src/finiteVolume/fields/fvPatchFields/derived/pressureInletVelocity/pressureInletVelocityFvPatchVectorField.H

@@ -155,15 +155,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressureNormalInletOutletVelocity/pressureNormalInletOutletVelocityFvPatchVectorField.H

@@ -171,15 +171,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/pressurePermeableAlphaInletOutletVelocity/pressurePermeableAlphaInletOutletVelocityFvPatchVectorField.H

@@ -194,13 +194,8 @@ public:
 
     // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/finiteVolume/fields/fvPatchFields/derived/supersonicFreestream/supersonicFreestreamFvPatchVectorField.C

@@ -76,7 +76,7 @@ supersonicFreestreamFvPatchVectorField
 
     if (!this->readValueEntry(dict))
     {
-        fvPatchField<vector>::operator=(patchInternalField());
+        fvPatchField<vector>::patchInternalField(*this);
     }
 
     refValue() = *this;

src/finiteVolume/fields/fvPatchFields/derived/uniformInletOutlet/uniformInletOutletFvPatchField.H

@@ -169,13 +169,8 @@ public:
 
     // Member functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Mapping functions

src/finiteVolume/fields/fvPatchFields/derived/variableHeightFlowRate/variableHeightFlowRateFvPatchField.C

@@ -82,13 +82,14 @@ Foam::variableHeightFlowRateFvPatchScalarField
     upperBound_(dict.get<scalar>("upperBound"))
 {
     fvPatchFieldBase::readDict(dict);
-    this->refValue() = 0.0;
 
     if (!this->readValueEntry(dict))
     {
-        fvPatchScalarField::operator=(this->patchInternalField());
+        // Fallback: set to the internal field
+        fvPatchField<scalar>::patchInternalField(*this);
     }
 
+    this->refValue() = 0.0;
     this->refGrad() = 0.0;
     this->valueFraction() = 0.0;
 }

src/finiteVolume/fields/fvPatchFields/fvPatchField/fvPatchField.C

@@ -169,7 +169,7 @@ Foam::fvPatchField<Type>::fvPatchField
     // For unmapped faces set to internal field value (zero-gradient)
     if (notNull(iF) && mapper.hasUnmapped())
     {
-        fvPatchField<Type>::operator=(this->patchInternalField());
+        fvPatchField<Type>::patchInternalField(*this);
     }
     this->map(ptf, mapper);
 }
@@ -241,7 +241,7 @@ void Foam::fvPatchField<Type>::autoMap
 
     if (!this->size() && !mapper.distributed())
     {
-        f.setSize(mapper.size());
+        f.resize_nocopy(mapper.size());
         if (f.size())
         {
             f = this->patchInternalField();

src/finiteVolume/fields/fvPatchFields/fvPatchField/fvPatchField.H

@@ -154,8 +154,59 @@ public:
     virtual ~fvPatchFieldBase() = default;
 
 
+    // Static Member Functions
+
+        //- The type name for \c empty patch fields
+        static const word& emptyType() noexcept
+        {
+            return Foam::fieldTypes::emptyType;
+        }
+
+        //- The type name for \c calculated patch fields
+        static const word& calculatedType() noexcept
+        {
+            return Foam::fieldTypes::calculatedType;
+        }
+
+        //- The type name for \c extrapolatedCalculated patch fields
+        //- combines \c zero-gradient and \c calculated
+        static const word& extrapolatedCalculatedType() noexcept
+        {
+            return Foam::fieldTypes::extrapolatedCalculatedType;
+        }
+
+        //- The type name for \c zeroGradient patch fields
+        static const word& zeroGradientType() noexcept
+        {
+            return Foam::fieldTypes::zeroGradientType;
+        }
+
+
     // Member Functions
 
+    // Attributes
+
+        //- True if the value of the patch field is altered by assignment
+        virtual bool assignable() const
+        {
+            return true;
+        }
+
+        //- True if the patch field fixes a value.
+        //  Needed to check if a level has to be specified while solving
+        //  Poissons equations.
+        virtual bool fixesValue() const
+        {
+            return false;
+        }
+
+        //- True if the patch field is coupled
+        virtual bool coupled() const
+        {
+            return false;
+        }
+
+
     // Access
 
         //- The associated objectRegistry
@@ -473,37 +524,6 @@ public:
 
     // Member Functions
 
-        //- The type name for calculated patch fields
-        static const word& calculatedType();
-
-        //- The type name for zeroGradient patch fields
-        static const word& zeroGradientType();
-
-
-    // Attributes
-
-        //- True if this patch field fixes a value.
-        //  Needed to check if a level has to be specified while solving
-        //  Poissons equations.
-        virtual bool fixesValue() const
-        {
-            return false;
-        }
-
-        //- True if the value of the patch field
-        //- is altered by assignment (the default)
-        virtual bool assignable() const
-        {
-            return true;
-        }
-
-        //- True if this patch field is coupled
-        virtual bool coupled() const
-        {
-            return false;
-        }
-
-
     // Access
 
         //- Return const-reference to the dimensioned internal field

src/finiteVolume/fields/fvsPatchFields/basic/calculated/calculatedFvsPatchField.C

@@ -29,14 +29,6 @@ License
 #include "calculatedFvsPatchField.H"
 #include "fvPatchFieldMapper.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-template<class Type>
-const Foam::word& Foam::fvsPatchField<Type>::calculatedType()
-{
-    return Foam::calculatedFvsPatchField<Type>::typeName;
-}
-
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class Type>

src/finiteVolume/fields/fvsPatchFields/basic/calculated/calculatedFvsPatchField.H

@@ -34,8 +34,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef calculatedFvsPatchField_H
+#ifndef Foam_calculatedFvsPatchField_H
-#define calculatedFvsPatchField_H
+#define Foam_calculatedFvsPatchField_H
 
 #include "fvsPatchField.H"
 
@@ -53,11 +53,10 @@ class calculatedFvsPatchField
 :
     public fvsPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName("calculated");
+    TypeName("calculated");  // fieldTypes::calculatedTypeName_()
 
 
     // Constructors
@@ -121,17 +120,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 };
 
 

src/finiteVolume/fields/fvsPatchFields/basic/fixedValue/fixedValueFvsPatchField.H

@@ -122,17 +122,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
         // Evaluation functions

src/finiteVolume/fields/fvsPatchFields/basic/sliced/slicedFvsPatchField.H

@@ -130,20 +130,13 @@ public:
     virtual ~slicedFvsPatchField<Type>();
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+        //- True: this patch field fixes a value.
-
+        virtual bool fixesValue() const { return true; }
-            //- Return true if this patch field fixes a value.
-            //  Needed to check if a level has to be specified while solving
-            //  Poissons equations.
-            virtual bool fixesValue() const
-            {
-                return true;
-            }
 
 
-    // Member operators
+    // Member Operators
 
         virtual void operator=(const UList<Type>&) {}
 

src/finiteVolume/fields/fvsPatchFields/constraint/empty/emptyFvsPatchField.H

@@ -34,8 +34,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef emptyFvsPatchField_H
+#ifndef Foam_emptyFvsPatchField_H
-#define emptyFvsPatchField_H
+#define Foam_emptyFvsPatchField_H
 
 #include "fvsPatchField.H"
 #include "emptyFvPatch.H"
@@ -54,11 +54,10 @@ class emptyFvsPatchField
 :
     public fvsPatchField<Type>
 {
-
 public:
 
     //- Runtime type information
-    TypeName(emptyFvPatch::typeName_());
+    TypeName(emptyFvPatch::typeName_());  // fieldTypes::emptyTypeName_()
 
 
     // Constructors

src/finiteVolume/fields/fvsPatchFields/fvsPatchField/fvsPatchField.H

@@ -126,8 +126,40 @@ public:
     virtual ~fvsPatchFieldBase() = default;
 
 
+    // Static Member Functions
+
+        //- The type name for \c empty patch fields
+        static const word& emptyType() noexcept
+        {
+            return Foam::fieldTypes::emptyType;
+        }
+
+        //- The type name for \c calculated patch fields
+        static const word& calculatedType() noexcept
+        {
+            return Foam::fieldTypes::calculatedType;
+        }
+
+
     // Member Functions
 
+    // Attributes
+
+        //- True if the patch field fixes a value.
+        //  Needed to check if a level has to be specified while solving
+        //  Poissons equations.
+        virtual bool fixesValue() const
+        {
+            return false;
+        }
+
+        //- True if the patch field is coupled
+        virtual bool coupled() const
+        {
+            return false;
+        }
+
+
     // Access
 
         //- The associated objectRegistry
@@ -403,27 +435,6 @@ public:
 
     // Member Functions
 
-        //- The type name for calculated patch fields
-        static const word& calculatedType();
-
-
-    // Attributes
-
-        //- True if this patch field fixes a value.
-        //  Needed to check if a level has to be specified while solving
-        //  Poissons equations.
-        virtual bool fixesValue() const
-        {
-            return false;
-        }
-
-        //- True if this patch field is coupled
-        virtual bool coupled() const
-        {
-            return false;
-        }
-
-
     // Access
 
         //- Return const-reference to the dimensioned internal field

src/finiteVolume/fields/volFields/volFieldsFwd.H

@@ -24,11 +24,8 @@ License
     You should have received a copy of the GNU General Public License
     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
-Namespace
-    Foam::fieldTypes
-
 Description
-    Collection of common field types
+    Forwards and collection of common volume field types
 
 SourceFiles
     volFields.C

src/functionObjects/field/externalCoupled/externalCoupledTemperatureMixed/externalCoupledTemperatureMixedFvPatchScalarField.C

@@ -160,7 +160,7 @@ externalCoupledTemperatureMixedFvPatchScalarField
         // or extrapolated value
         if (!this->readValueEntry(dict))
         {
-            fvPatchField<scalar>::operator=(this->patchInternalField());
+            fvPatchField<scalar>::patchInternalField(*this);
         }
 
         // Initialise as a fixed value

src/overset/oversetPolyPatch/oversetFvPatchField.C

@@ -113,7 +113,7 @@ Foam::oversetFvPatchField<Type>::oversetFvPatchField
     // Use 'value' supplied, or set to internal field
     if (!this->readValueEntry(dict))
     {
-        Field<Type>::operator=(this->patchInternalField());
+        fvPatchField<Type>::patchInternalField(*this);
     }
 }
 

src/regionModels/surfaceFilmModels/derivedFvPatchFields/filmHeightInletVelocity/filmHeightInletVelocityFvPatchVectorField.H

@@ -176,15 +176,10 @@ public:
         }
 
 
-    // Member functions
+    // Member Functions
 
-        // Attributes
+        //- True: this patch field is altered by assignment
-
+        virtual bool assignable() const { return true; }
-            //- Return true: this patch field is altered by assignment
-            virtual bool assignable() const
-            {
-                return true;
-            }
 
 
         // Access

src/thermoTools/derivedFvPatchFields/fixedIncidentRadiation/fixedIncidentRadiationFvPatchScalarField.C

@@ -86,8 +86,8 @@ fixedIncidentRadiationFvPatchScalarField
     else
     {
         // Still reading so cannot yet evaluate. Make up a value.
-        fvPatchField<scalar>::operator=(patchInternalField());
+        fvPatchField<scalar>::patchInternalField(*this);
-        gradient() = 0.0;
+        gradient() = Zero;
     }
 }
 

src/thermoTools/derivedFvPatchFields/wallFunctions/sorptionWallFunction/sorptionWallFunctionFvPatchScalarField.C

@@ -311,8 +311,9 @@ sorptionWallFunctionFvPatchScalarField::sorptionWallFunctionFvPatchScalarField
     }
     else
     {
-        fvPatchField<scalar>::operator=(patchInternalField());
+        // Fallback: set to zero-gradient
-        gradient() = 0.0;
+        fvPatchField<scalar>::patchInternalField(*this);
+        gradient() = Zero;
     }
 }
 

src/transportModels/interfaceProperties/alphaContactAngle/alphaContactAngleTwoPhaseFvPatchScalarField.C

@@ -80,7 +80,8 @@ alphaContactAngleTwoPhaseFvPatchScalarField
     }
     else
     {
-        fvPatchField<scalar>::operator=(patchInternalField());
+        // Fallback: set to zero-gradient
+        fvPatchField<scalar>::patchInternalField(*this);
         gradient() = Zero;
     }
 }