ENH: add ListOps find/found accepting a unary predicate (#1182)

- can also be used for other purposes.
  Eg,

      if (ListOps::found(list, matcher))
      {
         ...
      }

  vs.

      if (!findStrings(matcher, list).empty())
      {
         ...
      }

applications/test/ListOps/Test-ListOps.C

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2012-2013 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -32,6 +32,8 @@ Description
 #include "List.H"
 #include "SubList.H"
 #include "ListOps.H"
+#include "labelField.H"
+#include "MinMax.H"
 #include "face.H"
 
 using namespace Foam;
@@ -113,22 +115,40 @@ int main(int argc, char *argv[])
 
     Info<< nl << "Test lambda predicates:" << nl << endl;
 
-    List<label> test6(identity(11));
-    // shift range for general testing
-    std::for_each(test6.begin(), test6.end(), [](label& x){ x -= 4; });
+    List<label> test6(identity(11, -4));
 
-    Info<< "Subset of non-zero, even values: "
-        << subsetList
+    // Add multiplier for mpore interesting testing
+    std::for_each(test6.begin(), test6.end(), [](label& x){ x *= 3; });
+
+    // Randomize the list
+    std::random_shuffle(test6.begin(), test6.end());
+
+    Info<< "randomized input list: " << flatOutput(test6) << nl;
+
+    const auto evenNonZero = [](const label& x){ return x && !(x % 2); };
+
+    Info<< "location of first even/non-zero: "
+        << ListOps::find(test6, evenNonZero) << nl;
+
+    Info<< "find > 12 && divisible by 5 : "
+        << ListOps::find
            (
                test6,
-               [](const label& x){ return x && !(x % 2); }
-           ) << nl
-        << endl;
+               [](const label& x) { return x > 12 && !(x % 5); }
+           ) << nl;
 
-    test6.append(identity(13));
+    Info<< "Found >= 8 : "
+        << ListOps::found(test6, labelMinMax(8, labelMax)) << nl;
 
-    // Randomize the list
-    std::random_shuffle(test6.begin(), test6.end());
+    Info<< "Found >= 25 : "
+        << ListOps::found(test6, labelMinMax(25, labelMax)) << nl;
+
+
+    Info<< "Subset of non-zero, even values: "
+        << subsetList(test6, evenNonZero) << nl
+        << endl;
+
+    test6.append(identity(13, 12));
 
     Info<< "Randomized: " << flatOutput(test6) << endl;
     inplaceUniqueSort(test6);

applications/test/stringList/Test-stringList.C

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -26,6 +26,7 @@ Description
 \*---------------------------------------------------------------------------*/
 
 #include "stringListOps.H"
+#include "ListOps.H"
 #include "FlatOutput.H"
 #include "IOstreams.H"
 #include "StringStream.H"
@@ -57,10 +58,18 @@ int main(int argc, char *argv[])
     labelList matches = findStrings(regExp(".*ee.*"), strLst);
 
     Info<< "matches found for regexp .*ee.* :" << nl << matches << nl;
+
     forAll(matches, i)
     {
         Info<< " -> " << strLst[matches[i]] << nl;
     }
+
+    Info<< "Match found using ListOps = "
+        << ListOps::found(strLst, regExp(".*ee.*")) << nl;
+
+    Info<< "First index = "
+        << ListOps::find(strLst, regExp(".*ee.*")) << nl;
+
     Info<< endl;
 
     matches = findStrings(reLst, strLst);

src/OpenFOAM/containers/Lists/ListOps/ListOps.H

@@ -582,6 +582,32 @@ struct greater
 };
 
 
+//- Find index of the first occurrence that satisfies the predicate.
+//  When start is specified, any occurrences before start are ignored.
+//  Linear search.
+//  \return position in list or -1 if not found.
+template<class ListType, class UnaryPredicate>
+label find
+(
+    const ListType& input,
+    const UnaryPredicate& pred,
+    const label start=0
+);
+
+
+//- True if there is a value in the list that satisfies the predicate.
+//  When start is specified, any occurences before start are ignored.
+//  Linear search.
+//  \return true if found.
+template<class ListType, class UnaryPredicate>
+bool found
+(
+    const ListType& input,
+    const UnaryPredicate& pred,
+    const label start=0
+);
+
+
 //- Set various locations of the list with a specified value.
 //
 //  \param list the list to modify

src/OpenFOAM/containers/Lists/ListOps/ListOpsTemplates.C

@@ -1097,6 +1097,43 @@ void Foam::ListOps::uniqueEqOp<T>::operator()
 }
 
 
+template<class ListType, class UnaryPredicate>
+Foam::label Foam::ListOps::find
+(
+    const ListType& input,
+    const UnaryPredicate& pred,
+    const label start
+)
+{
+    const label len = input.size();
+
+    if (start >= 0)
+    {
+        for (label i = start; i < len; ++i)
+        {
+            if (pred(input[i]))
+            {
+                return i;
+            }
+        }
+    }
+
+    return -1;
+}
+
+
+template<class ListType, class UnaryPredicate>
+bool Foam::ListOps::found
+(
+    const ListType& input,
+    const UnaryPredicate& pred,
+    const label start
+)
+{
+    return (ListOps::find(input, pred, start) >= 0);
+}
+
+
 template<class T>
 void Foam::ListOps::setValue
 (

src/OpenFOAM/primitives/ranges/MinMax/MinMax.H

@@ -111,6 +111,7 @@ namespace Foam
 template<class T> class MinMax;
 
 // Common min/max types
+typedef MinMax<label> labelMinMax;
 typedef MinMax<scalar> scalarMinMax;
 
 

src/overset/cellCellStencil/trackingInverseDistance/voxelMeshSearch.C

@@ -425,7 +425,7 @@ Foam::label Foam::voxelMeshSearch::findCell(const point& p) const
                     label nei = mesh_.faceNeighbour()[facei];
                     nextCell = (own == celli ? nei : own);
 
-                    if (findIndex(track_, nextCell, startOfTrack) != -1)
+                    if (track_.found(nextCell, startOfTrack))
                     {
                         return celli;
                     }
@@ -438,7 +438,7 @@ Foam::label Foam::voxelMeshSearch::findCell(const point& p) const
                     {
                         return nextCell;
                     }
-                    else if (findIndex(track_, nextCell, startOfTrack) != -1)
+                    else if (track_.found(nextCell, startOfTrack))
                     {
                         return -1;  // point is really out
                     }

src/sampling/sampledSet/sampledSets/sampledSetsGrouping.C

@@ -26,8 +26,8 @@ License
 #include "sampledSets.H"
 #include "volFields.H"
 #include "IOobjectList.H"
-#include "stringListOps.H"
 #include "UIndirectList.H"
+#include "ListOps.H"
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
@@ -69,7 +69,7 @@ Foam::label Foam::sampledSets::classifyFields()
     // Detect missing fields
     forAll(fieldSelection_, i)
     {
-        if (findStrings(fieldSelection_[i], allFields).empty())
+        if (!ListOps::found(allFields, fieldSelection_[i]))
         {
             missed.append(i);
         }

src/sampling/sampledSurface/sampledSurfaces/sampledSurfacesGrouping.C

@@ -25,8 +25,8 @@ License
 
 #include "sampledSurfaces.H"
 #include "IOobjectList.H"
-#include "stringListOps.H"
 #include "UIndirectList.H"
+#include "ListOps.H"
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
@@ -57,7 +57,7 @@ Foam::label Foam::sampledSurfaces::classifyFields()
     // Detect missing fields
     forAll(fieldSelection_, i)
     {
-        if (findStrings(fieldSelection_[i], allFields).empty())
+        if (!ListOps::found(allFields, fieldSelection_[i]))
         {
             missed.append(i);
         }

src/sampling/surface/isoSurface/isoSurfaceTopo.C

@@ -641,7 +641,7 @@ void Foam::isoSurfaceTopo::generateTriPoints
         forAll(f1, fp)
         {
             oppositeI = f1[fp];
-            if (findIndex(f0, oppositeI) == -1)
+            if (!f0.found(oppositeI))
             {
                 break;
             }