From 0250a1b0bbafd4c1270afed667bc5a0cced41fc2 Mon Sep 17 00:00:00 2001
From: Mark Olesen <Mark.Olesen@esi-group.com>
Date: Wed, 30 Aug 2023 14:54:36 +0200
Subject: [PATCH] ENH: support List sub-slice searching, use std::find()

- support UList shallowCopy with pointer/size
  (eg, for slicing into or from span)

ENH: add SubList::reset() functionality

- allows modification of a SubList after construction.
  Previously a SubList had an immutable location after construction
  and there was no way to shift or change its location.

BUG: missed special handling for DynamicList<char>::readList (fixes #2974)

- equivalent to List<char>::readList, in which the stream is
  temporarily toggled from ASCII to BINARY when reading in a List of
  char data.
  This specialization was missed when DynamicList<T>::readList() was
  fully implemented.
---
 applications/test/SubField/Test-SubField.C    |  40 +++++--
 .../containers/Buffers/CircularBuffer.C       |   2 +
 .../containers/Buffers/CircularBuffer.H       |  15 ++-
 .../containers/Buffers/CircularBufferI.H      |   7 ++
 .../IndirectListBase/IndirectListBase.C       |  18 ++-
 .../IndirectListBase/IndirectListBase.H       |  22 ++--
 .../IndirectListBase/IndirectListBaseI.H      |   5 +-
 .../Lists/DynamicList/DynamicListIO.C         |  21 ++++
 .../containers/Lists/FixedList/FixedList.C    |  47 +++++---
 .../containers/Lists/FixedList/FixedList.H    |  30 +++--
 .../containers/Lists/FixedList/FixedListI.H   |  17 ++-
 src/OpenFOAM/containers/Lists/List/SubList.H  |  45 ++++++-
 src/OpenFOAM/containers/Lists/List/SubListI.H | 110 +++++++++++++++++-
 src/OpenFOAM/containers/Lists/List/UList.C    |  42 ++++---
 src/OpenFOAM/containers/Lists/List/UList.H    |  31 +++--
 src/OpenFOAM/containers/Lists/List/UListI.H   |  24 +++-
 src/OpenFOAM/containers/Lists/List/UListIO.C  |   5 +-
 .../containers/Lists/List/stdVectorIO.C       |   3 +-
 src/OpenFOAM/fields/Fields/Field/SubField.H   |   2 +-
 19 files changed, 391 insertions(+), 95 deletions(-)

diff --git a/applications/test/SubField/Test-SubField.C b/applications/test/SubField/Test-SubField.C
index 4e89c0cda3..0b1b3c64ca 100644
--- a/applications/test/SubField/Test-SubField.C
+++ b/applications/test/SubField/Test-SubField.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2019 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -37,6 +37,7 @@ Description
 #include "scalarField.H"
 #include "SubField.H"
 #include "labelRange.H"
+#include "ListOps.H"
 #include <numeric>
 
 using namespace Foam;
@@ -57,26 +58,26 @@ int main(int argc, char *argv[])
     argList::noFunctionObjects();
 
     {
-        List<scalar> ident(25);
+        List<label> ident(25);
         std::iota(ident.begin(), ident.end(), 0);
 
         print(ident);
 
-        SubList<scalar>(ident, 10) = -10;
+        SubList<label>(ident, 10) = -10;
         print(ident);
 
-        SubField<scalar>(ident, 10) = 10;
+        SubField<label>(ident, 10) = 10;
         print(ident);
 
-        SubField<scalar>(ident, 10) += 10;
+        SubField<label>(ident, 10) += 10;
         print(ident);
 
-        SubField<scalar>{ident, 10, 10} *= 5;
+        SubField<label>{ident, 10, 10} *= 5;
         print(ident);
 
 
         // NOTE: Need {} instead of ()
-        // SubList<scalar>(ident) = 100;
+        // SubList<label>(ident) = 100;
 
         // GCC
         // error: conflicting declaration 'Foam::SubList<double> ident'
@@ -85,7 +86,30 @@ int main(int argc, char *argv[])
         // warning: parentheses were disambiguated as redundant parentheses
         // around declaration of variable named 'ident' [-Wvexing-parse]
 
-        SubList<scalar>{ident} = 100;
+        SubList<label>{ident} = 100;
+        print(ident);
+
+        SubList<label> sub(ident);
+        sub = 1;
+        print(sub);
+
+        sub.reset(ident, labelRange(4, 5)) = 5;
+        print(sub);
+        print(ident);
+
+        sub.reset(ident, labelRange(14, 5)) = 15;
+        print(sub);
+        print(ident);
+
+        // Cryptic, probably not a great idea to write this
+        sub.reset(ident, {20, 3}) = -1;
+        print(sub);
+        print(ident);
+
+        // This is also possible since we hold a concrete pointer/size
+        // and not an intermediate
+        ListOps::identity(sub.reset(ident, 8, 8));
+        print(sub);
         print(ident);
     }
 
diff --git a/src/OpenFOAM/containers/Buffers/CircularBuffer.C b/src/OpenFOAM/containers/Buffers/CircularBuffer.C
index d095a58334..30e1661320 100644
--- a/src/OpenFOAM/containers/Buffers/CircularBuffer.C
+++ b/src/OpenFOAM/containers/Buffers/CircularBuffer.C
@@ -108,6 +108,8 @@ const Foam::SubList<T> Foam::CircularBuffer<T>::array_two() const
 template<class T>
 Foam::label Foam::CircularBuffer<T>::find(const T& val, label pos) const
 {
+    if (pos < 0) return -1;  // no-op
+
     label i = -1;
 
     const auto list1 = this->array_one();
diff --git a/src/OpenFOAM/containers/Buffers/CircularBuffer.H b/src/OpenFOAM/containers/Buffers/CircularBuffer.H
index c5f0519bff..2c19b78444 100644
--- a/src/OpenFOAM/containers/Buffers/CircularBuffer.H
+++ b/src/OpenFOAM/containers/Buffers/CircularBuffer.H
@@ -282,18 +282,21 @@ public:
 
     // Search
 
+        //- True if the value is contained in the list.
+        inline bool contains(const T& val) const;
+
+        //- Is the value contained in the list?
+        //  \param val The value to search for
+        //  \param pos The first position to examine (no-op if -ve)
+        //  \return true if found.
+        inline bool contains(const T& val, label pos) const;
+
         //- Find index of the first occurrence of the value.
         //  Any occurrences before the start pos are ignored.
         //  Linear search.
         //  \return position in list or -1 if not found.
         label find(const T& val, label pos = 0) const;
 
-        //- Is the value contained in the list?
-        //  Linear search from start pos until the end of the list.
-        //  Any occurrences before the start pos are ignored.
-        //  \return true if found.
-        inline bool contains(const T& val, label pos = 0) const;
-
 
     // Stack-like Operations
 
diff --git a/src/OpenFOAM/containers/Buffers/CircularBufferI.H b/src/OpenFOAM/containers/Buffers/CircularBufferI.H
index 2690338d9b..b7f71671f6 100644
--- a/src/OpenFOAM/containers/Buffers/CircularBufferI.H
+++ b/src/OpenFOAM/containers/Buffers/CircularBufferI.H
@@ -255,6 +255,13 @@ inline void Foam::CircularBuffer<T>::reserve_nocopy(const label len)
 }
 
 
+template<class T>
+bool Foam::CircularBuffer<T>::contains(const T& val) const
+{
+    return (this->array_one().contains(val) || this->array_two().contains(val));
+}
+
+
 template<class T>
 inline bool Foam::CircularBuffer<T>::contains(const T& val, label pos) const
 {
diff --git a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.C b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.C
index 2243f3d8bc..397b3792d5 100644
--- a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.C
+++ b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.C
@@ -31,13 +31,21 @@ template<class T, class Addr>
 Foam::label Foam::IndirectListBase<T, Addr>::find
 (
     const T& val,
-    label pos
+    label pos,
+    label len
 ) const
 {
-    const label len = addr_.size();
-
-    if (pos >= 0 && len)
+    if (pos >= 0 && pos < addr_.size())
     {
+        // Change sub-length to (one-past) end position
+        // len == -1 (like std::string::npos) - search until end
+
+        if (len > 0) len += pos;
+        if (len < 0 || len > addr_.size())
+        {
+            len = addr_.size();
+        }
+
         const T* const vals = values_.begin();
 
         while (pos < len)
@@ -62,7 +70,7 @@ Foam::label Foam::IndirectListBase<T, Addr>::rfind
     label pos
 ) const
 {
-    // pos == -1 has same meaning as std::string::npos - search from end
+    // pos == -1 (like std::string::npos) - search from end
 
     if (pos < 0 || pos >= addr_.size())
     {
diff --git a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.H b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.H
index 873c43051a..03caf4f4fa 100644
--- a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.H
+++ b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBase.H
@@ -179,11 +179,19 @@ public:
 
     // Search
 
+        //- Is the value contained in the list?
+        //  \param val The value to search for
+        //  \param pos The first position to examine (default: 0, no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return true if found.
+        inline bool contains(const T& val, label pos = 0, label len = -1) const;
+
         //- Find index of the first occurrence of the value.
-        //  Any occurrences before the start pos are ignored.
-        //  Linear search.
-        //  \return -1 if not found.
-        label find(const T& val, label pos = 0) const;
+        //  \param val The value to search for
+        //  \param pos The first position to examine (default: 0, no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return position in list or -1 if not found.
+        label find(const T& val, label pos = 0, label len = -1) const;
 
         //- Find index of the last occurrence of the value.
         //  Any occurrences after the end pos are ignored.
@@ -191,12 +199,6 @@ public:
         //  \return -1 if not found.
         label rfind(const T& val, label pos = -1) const;
 
-        //- Is the value contained in the list?
-        //  Linear search from start pos until the end of the list.
-        //  Any occurrences before the start pos are ignored.
-        //  \return true if found.
-        inline bool contains(const T& val, label pos = 0) const;
-
 
     // Member Operators
 
diff --git a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBaseI.H b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBaseI.H
index f682f0c8bc..abb311cfd9 100644
--- a/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBaseI.H
+++ b/src/OpenFOAM/containers/IndirectLists/IndirectListBase/IndirectListBaseI.H
@@ -102,10 +102,11 @@ template<class T, class Addr>
 inline bool Foam::IndirectListBase<T, Addr>::contains
 (
     const T& val,
-    label pos
+    label pos,
+    label len
 ) const
 {
-    return (this->find(val, pos) >= 0);
+    return (this->find(val, pos, len) >= 0);
 }
 
 
diff --git a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListIO.C b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListIO.C
index aa79152c52..c4a2dbae33 100644
--- a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListIO.C
+++ b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListIO.C
@@ -222,6 +222,27 @@ Foam::Istream& Foam::DynamicList<T, SizeMin>::readList(Istream& is)
                 );
             }
         }
+        else if (std::is_same<char, T>::value)
+        {
+            // Special treatment for char data (always binary and contiguous)
+            // (see List<char>::readList)
+
+            if (len)
+            {
+                const auto oldFmt = is.format(IOstreamOption::BINARY);
+
+                // read(...) includes surrounding start/end delimiters
+                is.read(list.data_bytes(), list.size_bytes());
+
+                is.format(oldFmt);
+
+                is.fatalCheck
+                (
+                    "DynamicList<char>::readList(Istream&) : "
+                    "reading binary block"
+                );
+            }
+        }
         else
         {
             // Begin of contents marker
diff --git a/src/OpenFOAM/containers/Lists/FixedList/FixedList.C b/src/OpenFOAM/containers/Lists/FixedList/FixedList.C
index 01e7752c18..df7410feba 100644
--- a/src/OpenFOAM/containers/Lists/FixedList/FixedList.C
+++ b/src/OpenFOAM/containers/Lists/FixedList/FixedList.C
@@ -46,24 +46,42 @@ std::streamsize Foam::FixedList<T, N>::byteSize()
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class T, unsigned N>
-Foam::label Foam::FixedList<T, N>::find(const T& val, label pos) const
+Foam::label Foam::FixedList<T, N>::find(const T& val) const
 {
-    if (pos >= 0)
+    const auto iter = std::find(this->cbegin(), this->cend(), val);
+    return (iter != this->cend() ? label(iter - this->cbegin()) : label(-1));
+}
+
+
+template<class T, unsigned N>
+Foam::label Foam::FixedList<T, N>::find
+(
+    const T& val,
+    label pos,
+    label len
+) const
+{
+    if (pos >= 0 && pos < label(N))
     {
-        // auto iter = std::find(this->begin(pos), this->end(), val);
-        // if (iter != this->end())
-        // {
-        //     return label(iter - this->begin());
-        // }
+        // Change sub-length to (one-past) end position
+        // len == -1 (like std::string::npos) - search until end
 
-        while (pos < label(N))
+        if (len > 0) len += pos;
+        if (len < 0 || len > label(N))
         {
-            if (this->v_[pos] == val)
-            {
-                return pos;
-            }
+            len = label(N);
+        }
 
-            ++pos;
+        const auto iter = std::find
+        (
+            (this->cbegin() + pos),
+            (this->cbegin() + len),
+            val
+        );
+
+        if (iter != (this->cbegin() + len))
+        {
+            return label(iter - this->cbegin());
         }
     }
 
@@ -74,7 +92,8 @@ Foam::label Foam::FixedList<T, N>::find(const T& val, label pos) const
 template<class T, unsigned N>
 Foam::label Foam::FixedList<T, N>::rfind(const T& val, label pos) const
 {
-    // pos == -1 has same meaning as std::string::npos - search from end
+    // pos == -1 (like std::string::npos) - search from end
+
     if (pos < 0 || pos >= label(N))
     {
         pos = label(N)-1;
diff --git a/src/OpenFOAM/containers/Lists/FixedList/FixedList.H b/src/OpenFOAM/containers/Lists/FixedList/FixedList.H
index 9a3f190d80..59e1188bee 100644
--- a/src/OpenFOAM/containers/Lists/FixedList/FixedList.H
+++ b/src/OpenFOAM/containers/Lists/FixedList/FixedList.H
@@ -275,11 +275,27 @@ public:
 
     // Search
 
+        //- True if the value is contained in the list.
+        inline bool contains(const T& val) const;
+
+        //- Is the value contained in the list?
+        //  \param val The value to search for
+        //  \param pos The first position to examine (no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return true if found.
+        inline bool contains(const T& val, label pos, label len = -1) const;
+
         //- Find index of the first occurrence of the value.
-        //  Any occurrences before the start pos are ignored.
-        //  Linear search.
-        //  \return -1 if not found.
-        label find(const T& val, label pos = 0) const;
+        //  \param val The value to search for
+        //  \return position in list or -1 if not found.
+        label find(const T& val) const;
+
+        //- Find index of the first occurrence of the value.
+        //  \param val The value to search for
+        //  \param pos The first position to examine (no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return position in list or -1 if not found.
+        label find(const T& val, label pos, label len = -1) const;
 
         //- Find index of the last occurrence of the value.
         //  Any occurrences after the end pos are ignored.
@@ -287,12 +303,6 @@ public:
         //  \return position in list or -1 if not found.
         label rfind(const T& val, label pos = -1) const;
 
-        //- Is the value contained in the list?
-        //  Linear search from start pos until the end of the list.
-        //  Any occurrences before the start pos are ignored.
-        //  \return true if found.
-        inline bool contains(const T& val, label pos = 0) const;
-
 
     // Edit
 
diff --git a/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H b/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
index 95b45f4c6b..4bef6f07b3 100644
--- a/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
+++ b/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
@@ -307,9 +307,22 @@ inline bool Foam::FixedList<T, N>::uniform() const
 
 
 template<class T, unsigned N>
-inline bool Foam::FixedList<T, N>::contains(const T& val, label pos) const
+inline bool Foam::FixedList<T, N>::contains(const T& val) const
 {
-    return (this->find(val, pos) >= 0);
+    const auto iter = std::find(this->cbegin(), this->cend(), val);
+    return (iter != this->cend());
+}
+
+
+template<class T, unsigned N>
+inline bool Foam::FixedList<T, N>::contains
+(
+    const T& val,
+    label pos,
+    label len
+) const
+{
+    return (this->find(val, pos, len) >= 0);
 }
 
 
diff --git a/src/OpenFOAM/containers/Lists/List/SubList.H b/src/OpenFOAM/containers/Lists/List/SubList.H
index addd12055d..f1c6aa2b38 100644
--- a/src/OpenFOAM/containers/Lists/List/SubList.H
+++ b/src/OpenFOAM/containers/Lists/List/SubList.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2021 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -89,7 +89,7 @@ public:
     // Constructors
 
         //- Construct from UList, the entire size
-        inline explicit SubList(const UList<T>& list);
+        inline explicit SubList(const UList<T>& list) noexcept;
 
         //- Construct from FixedList, the entire size
         template<unsigned N>
@@ -128,6 +128,47 @@ public:
         );
 
 
+    // Member Functions
+
+        //- Reset to zero-sized and nullptr
+        inline UList<T>& reset(std::nullptr_t) noexcept;
+
+        //- Reset to use entire UList
+        inline UList<T>& reset(const UList<T>& list) noexcept;
+
+        //- Reset to use UList with sub-list size, start at 0
+        inline UList<T>& reset
+        (
+            const UList<T>& list,
+            const label subSize
+        );
+
+        //- Reset to use UList with sub-list size and start index
+        inline UList<T>& reset
+        (
+            const UList<T>& list,
+            const label subSize,
+            const label startIndex
+        );
+
+        //- Reset to use UList with a (start,size) range.
+        //  The range is subsetted with the list size itself to ensure that the
+        //  result always addresses a valid section of the list.
+        inline UList<T>& reset
+        (
+            const UList<T>& list,
+            const labelRange& range
+        );
+
+        //- Reset to use UList with a (start,size) range, but bypassing
+        //- run-time range checking.
+        inline UList<T>& reset
+        (
+            const labelRange& range,
+            const UList<T>& list
+        );
+
+
     // Member Operators
 
         //- Allow cast to a const List\<T\>&
diff --git a/src/OpenFOAM/containers/Lists/List/SubListI.H b/src/OpenFOAM/containers/Lists/List/SubListI.H
index 29422f1bd4..389e9e85f8 100644
--- a/src/OpenFOAM/containers/Lists/List/SubListI.H
+++ b/src/OpenFOAM/containers/Lists/List/SubListI.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2021 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -28,13 +28,22 @@ License
 
 #include "FixedList.H"
 
+// * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
+
+template<class T>
+inline const Foam::SubList<T>& Foam::SubList<T>::null()
+{
+    return NullObjectRef<SubList<T>>();
+}
+
+
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class T>
 inline Foam::SubList<T>::SubList
 (
     const UList<T>& list
-)
+) noexcept
 :
     UList<T>(const_cast<T*>(list.cdata()), list.size())
 {}
@@ -113,9 +122,102 @@ inline Foam::SubList<T>::SubList
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class T>
-inline const Foam::SubList<T>& Foam::SubList<T>::null()
+inline Foam::UList<T>& Foam::SubList<T>::reset(std::nullptr_t) noexcept
 {
-    return NullObjectRef<SubList<T>>();
+    UList<T>::shallowCopy(nullptr, 0);
+    return *this;
+}
+
+
+template<class T>
+inline Foam::UList<T>& Foam::SubList<T>::reset
+(
+    const UList<T>& list
+) noexcept
+{
+    UList<T>::shallowCopy(list);
+    return *this;
+}
+
+
+template<class T>
+inline Foam::UList<T>& Foam::SubList<T>::reset
+(
+    const UList<T>& list,
+    const label subSize
+)
+{
+    #ifdef FULLDEBUG
+    list.checkSize(subSize);
+    #endif
+
+    UList<T>::shallowCopy(const_cast<T*>(list.cdata()), subSize);
+    return *this;
+}
+
+
+template<class T>
+inline Foam::UList<T>& Foam::SubList<T>::reset
+(
+    const UList<T>& list,
+    const label subSize,
+    const label startIndex
+)
+{
+    #ifdef FULLDEBUG
+    list.checkRange(startIndex, subSize);
+    #endif
+
+    UList<T>::shallowCopy
+    (
+        const_cast<T*>(list.cdata() + startIndex),
+        subSize
+    );
+    return *this;
+}
+
+
+template<class T>
+inline Foam::UList<T>& Foam::SubList<T>::reset
+(
+    const UList<T>& list,
+    const labelRange& range
+)
+{
+    #ifdef FULLDEBUG
+    // subset0() always produces valid ranges but want to check
+    // that the input itself was valid
+    list.checkRange(range.start(), range.size());
+    #endif
+
+    labelRange clamped(range.subset0(list.size()));
+
+    UList<T>::shallowCopy
+    (
+        const_cast<T*>(list.cdata() + clamped.start()),
+        clamped.size()
+    );
+    return *this;
+}
+
+
+template<class T>
+inline Foam::UList<T>& Foam::SubList<T>::reset
+(
+    const labelRange& range,
+    const UList<T>& list
+)
+{
+    #ifdef FULLDEBUG
+    list.checkRange(range.start(), range.size());
+    #endif
+
+    UList<T>::shallowCopy
+    (
+        const_cast<T*>(list.cdata() + range.start()),
+        range.size()
+    );
+    return *this;
 }
 
 
diff --git a/src/OpenFOAM/containers/Lists/List/UList.C b/src/OpenFOAM/containers/Lists/List/UList.C
index b8cc5f7b81..1860924305 100644
--- a/src/OpenFOAM/containers/Lists/List/UList.C
+++ b/src/OpenFOAM/containers/Lists/List/UList.C
@@ -177,26 +177,37 @@ std::streamsize Foam::UList<T>::byteSize() const
 
 
 template<class T>
-Foam::label Foam::UList<T>::find(const T& val, label pos) const
+Foam::label Foam::UList<T>::find(const T& val) const
 {
-    const label len = this->size();
+    const auto iter = std::find(this->cbegin(), this->cend(), val);
+    return (iter != this->cend() ? label(iter - this->cbegin()) : label(-1));
+}
 
-    if (pos >= 0)
+
+template<class T>
+Foam::label Foam::UList<T>::find(const T& val, label pos, label len) const
+{
+    if (pos >= 0 && pos < this->size())
     {
-        // auto iter = std::find(this->begin(pos), this->end(), val);
-        // if (iter != this->end())
-        // {
-        //     return label(iter - this->begin());
-        // }
+        // Change sub-length to (one-past) end position
+        // len == -1 (like std::string::npos) - search until end
 
-        while (pos < len)
+        if (len > 0) len += pos;
+        if (len < 0 || len > this->size())
         {
-            if (this->v_[pos] == val)
-            {
-                return pos;
-            }
+            len = this->size();
+        }
 
-            ++pos;
+        const auto iter = std::find
+        (
+            (this->cbegin() + pos),
+            (this->cbegin() + len),
+            val
+        );
+
+        if (iter != (this->cbegin() + len))
+        {
+            return label(iter - this->cbegin());
         }
     }
 
@@ -207,7 +218,8 @@ Foam::label Foam::UList<T>::find(const T& val, label pos) const
 template<class T>
 Foam::label Foam::UList<T>::rfind(const T& val, label pos) const
 {
-    // pos == -1 has same meaning as std::string::npos - search from end
+    // pos == -1 (like std::string::npos) - search from end
+
     if (pos < 0 || pos >= this->size())
     {
         pos = this->size()-1;
diff --git a/src/OpenFOAM/containers/Lists/List/UList.H b/src/OpenFOAM/containers/Lists/List/UList.H
index b88f5ade23..1d70c02703 100644
--- a/src/OpenFOAM/containers/Lists/List/UList.H
+++ b/src/OpenFOAM/containers/Lists/List/UList.H
@@ -318,11 +318,27 @@ public:
 
     // Search
 
+        //- True if the value is contained in the list.
+        inline bool contains(const T& val) const;
+
+        //- Is the value contained in the list?
+        //  \param val The value to search for
+        //  \param pos The first position to examine (no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return true if found.
+        inline bool contains(const T& val, label pos, label len = -1) const;
+
         //- Find index of the first occurrence of the value.
-        //  Any occurrences before the start pos are ignored.
-        //  Linear search.
+        //  \param val The value to search for
         //  \return position in list or -1 if not found.
-        label find(const T& val, label pos = 0) const;
+        label find(const T& val) const;
+
+        //- Find index of the first occurrence of the value.
+        //  \param val The value to search for
+        //  \param pos The first position to examine (no-op if -ve)
+        //  \param len The length of the search region (-ve until the end)
+        //  \return position in list or -1 if not found.
+        label find(const T& val, label pos, label len = -1) const;
 
         //- Find index of the last occurrence of the value.
         //  Any occurrences after the end pos are ignored.
@@ -330,12 +346,6 @@ public:
         //  \return position in list or -1 if not found.
         label rfind(const T& val, label pos = -1) const;
 
-        //- Is the value contained in the list?
-        //  Linear search from start pos until the end of the list.
-        //  Any occurrences before the start pos are ignored.
-        //  \return true if found.
-        inline bool contains(const T& val, label pos = 0) const;
-
 
     // Edit
 
@@ -354,6 +364,9 @@ public:
 
     // Copy
 
+        //- Copy the pointer and size
+        inline void shallowCopy(T* __restrict__ ptr, const label len) noexcept;
+
         //- Copy the pointer and size held by the given UList
         inline void shallowCopy(const UList<T>& list) noexcept;
 
diff --git a/src/OpenFOAM/containers/Lists/List/UListI.H b/src/OpenFOAM/containers/Lists/List/UListI.H
index 711785a304..b143475599 100644
--- a/src/OpenFOAM/containers/Lists/List/UListI.H
+++ b/src/OpenFOAM/containers/Lists/List/UListI.H
@@ -304,9 +304,29 @@ inline std::streamsize Foam::UList<T>::size_bytes() const noexcept
 
 
 template<class T>
-inline bool Foam::UList<T>::contains(const T& val, label pos) const
+inline bool Foam::UList<T>::contains(const T& val) const
 {
-    return (this->find(val, pos) >= 0);
+    const auto iter = std::find(this->begin(), this->end(), val);
+    return (iter != this->end());
+}
+
+
+template<class T>
+inline bool Foam::UList<T>::contains(const T& val, label pos, label len) const
+{
+    return (this->find(val, pos, len) >= 0);
+}
+
+
+template<class T>
+inline void Foam::UList<T>::shallowCopy
+(
+    T* __restrict__ ptr,
+    const label len
+) noexcept
+{
+    size_ = len;
+    v_ = ptr;
 }
 
 
diff --git a/src/OpenFOAM/containers/Lists/List/UListIO.C b/src/OpenFOAM/containers/Lists/List/UListIO.C
index afc7dcb0f3..93ff35f190 100644
--- a/src/OpenFOAM/containers/Lists/List/UListIO.C
+++ b/src/OpenFOAM/containers/Lists/List/UListIO.C
@@ -187,10 +187,7 @@ Foam::Istream& Foam::UList<T>::readList(Istream& is)
                 << exit(FatalIOError);
         }
 
-        for (label i = 0; i < len; ++i)
-        {
-            list[i] = std::move(elems[i]);
-        }
+        std::move(elems.begin(), elems.end(), list.begin());
     }
     else if (tok.isLabel())
     {
diff --git a/src/OpenFOAM/containers/Lists/List/stdVectorIO.C b/src/OpenFOAM/containers/Lists/List/stdVectorIO.C
index a11964a66a..d3359cd864 100644
--- a/src/OpenFOAM/containers/Lists/List/stdVectorIO.C
+++ b/src/OpenFOAM/containers/Lists/List/stdVectorIO.C
@@ -42,11 +42,12 @@ Foam::Ostream& Foam::operator<<(Ostream& os, const std::vector<T>& list)
 
     os << label(list.size()) << token::BEGIN_LIST;
 
+    // Contents
     if (iter != last)
     {
         os << *iter;
 
-        while (++iter != last)
+        for (++iter; (iter != last); (void)++iter)
         {
             os << token::SPACE << *iter;
         }
diff --git a/src/OpenFOAM/fields/Fields/Field/SubField.H b/src/OpenFOAM/fields/Fields/Field/SubField.H
index 90a0482490..5634a9736d 100644
--- a/src/OpenFOAM/fields/Fields/Field/SubField.H
+++ b/src/OpenFOAM/fields/Fields/Field/SubField.H
@@ -172,7 +172,7 @@ public:
 
 #include "SubFieldI.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+// * * * * * * * * * * * * * * * Implementations * * * * * * * * * * * * * * //
 
 template<class Type>
 Foam::SubField<Type>