ENH: freshen code in labelRange classes

- misc improvements in functionality.

applications/test/labelRanges/Test-labelRanges.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) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -58,6 +58,7 @@ int main(int argc, char *argv[])
     }
 
 
+    labelRange range;
     labelRanges ranges;
 
     bool removeMode = false;
@@ -74,14 +75,16 @@ int main(int argc, char *argv[])
             continue;
         }
 
-        label start = 0;
+        {
-        label size  = 0;
+            label start = 0;
+            label size  = 0;
 
-        IStringStream(args[argI])() >> start;
+            IStringStream(args[argI])() >> start;
-        ++argI;
+            ++argI;
-        IStringStream(args[argI])() >> size;
+            IStringStream(args[argI])() >> size;
 
-        labelRange range(start, size);
+            range.reset(start, size);
+        }
 
         Info<< "---------------" << nl;
         if (removeMode)
@@ -107,10 +110,11 @@ int main(int argc, char *argv[])
             ranges.add(range);
         }
 
-        Info<< "<list>" << ranges << "</list>" << nl;
+        Info<< "<list>" << ranges << "</list>" << nl
-        forAllConstIter(labelRanges, ranges, iter)
+            << "content:";
+        for (auto i : ranges)
         {
-            Info<< " " << iter();
+            Info<< " " << i;
         }
         Info<< nl;
     }

src/OpenFOAM/primitives/ranges/labelRange/labelRange.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) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -29,8 +29,6 @@ License
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
-const Foam::labelRange::const_iterator Foam::labelRange::endIter_;
-
 int Foam::labelRange::debug(::Foam::debug::debugSwitch("labelRange", 0));
 
 
@@ -47,13 +45,24 @@ Foam::labelRange::labelRange(Istream& is)
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-bool Foam::labelRange::intersects
+void Foam::labelRange::adjust()
-(
-    const labelRange& range,
-    const bool touches
-) const
 {
-    label final = touches ? 1 : 0;
+    if (start_ < 0)
+    {
+        size_ += start_;
+        start_ = 0;
+    }
+
+    if (size_ < 0)
+    {
+        size_ = 0;
+    }
+}
+
+
+bool Foam::labelRange::overlaps(const labelRange& range, bool touches) const
+{
+    const label final = touches ? 1 : 0;
 
     return
     (
@@ -97,7 +106,7 @@ Foam::labelRange Foam::labelRange::join(const labelRange& range) const
 
 // * * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * //
 
-Foam::labelRange& Foam::labelRange::operator+=(const labelRange& rhs)
+void Foam::labelRange::operator+=(const labelRange& rhs)
 {
     if (!size_)
     {
@@ -112,8 +121,6 @@ Foam::labelRange& Foam::labelRange::operator+=(const labelRange& rhs)
         start_ = lower;
         size_  = upper - lower + 1;
     }
-
-    return *this;
 }
 
 
@@ -127,10 +134,10 @@ Foam::Istream& Foam::operator>>(Istream& is, labelRange& range)
 
     is.check("operator>>(Istream&, labelRange&)");
 
-    // disallow invalid sizes
+    // Disallow invalid sizes
-    if (range.size_ <= 0)
+    if (range.size_ < 0)
     {
-        range.clear();
+        range.size_ = 0;
     }
 
     return is;
@@ -139,15 +146,11 @@ Foam::Istream& Foam::operator>>(Istream& is, labelRange& range)
 
 Foam::Ostream& Foam::operator<<(Ostream& os, const labelRange& range)
 {
-    // write ASCII only for now
+    // Write ASCII only for now
     os  << token::BEGIN_LIST
         << range.start_ << token::SPACE << range.size_
         << token::END_LIST;
 
-//    os  << token::BEGIN_BLOCK
-//        << range.start_ << "-" << range.last()
-//        << token::END_BLOCK;
-
     os.check("operator<<(Ostream&, const labelRange&)");
     return os;
 }

src/OpenFOAM/primitives/ranges/labelRange/labelRange.H

@@ -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) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -25,7 +25,7 @@ Class
     Foam::labelRange
 
 Description
-    A label range specifier.
+    A range of labels.
 
 SourceFiles
     labelRange.C
@@ -47,8 +47,8 @@ class Ostream;
 
 // Forward declaration of friend functions and operators
 class labelRange;
-Istream& operator>>(Istream&, labelRange&);
+Istream& operator>>(Istream& is, labelRange& range);
-Ostream& operator<<(Ostream&, const labelRange&);
+Ostream& operator<<(Ostream& os, const labelRange& range);
 
 /*---------------------------------------------------------------------------*\
                          Class labelRange Declaration
@@ -63,7 +63,7 @@ class labelRange
 
 public:
 
-        static int debug;
+    static int debug;
 
 
     // Public classes
@@ -75,31 +75,50 @@ public:
 
             bool operator()(const labelRange& a, const labelRange& b)
             {
-                return a.first() < b.first();
+                return a.operator<(b);
             }
         };
 
+
     // Constructors
 
-        //- Construct an empty range
+        //- Construct an empty range with zero as start and size.
         inline labelRange();
 
-        //- Construct a range
+        //- Construct a range from start and size.
-        //  A negative size is autmatically changed to zero.
+        //  Optionally adjust the start to avoid any negative indices.
-        inline labelRange(const label start, const label size);
+        //  Always reduce a negative size to zero.
+        inline labelRange
+        (
+            const label start,
+            const label size,
+            const bool adjustStart = false
+        );
 
         //- Construct from Istream.
-        labelRange(Istream&);
+        labelRange(Istream& is);
 
 
     // Member Functions
 
-        //- Reset to zero size
+        //- Alias for setSize(const label)
+        inline void resize(const label n);
+
+        //- Adjust size
+        inline void setSize(const label n);
+
+        //- Reset to zero start and zero size
         inline void clear();
 
         //- Is the range empty?
         inline bool empty() const;
 
+        //- Adjust the start to avoid any negative indices
+        void adjust();
+
+        //- Is the range valid (non-empty)?
+        inline bool valid() const;
+
         //- Return the effective size of the range
         inline label size() const;
 
@@ -109,32 +128,44 @@ public:
         //- The (inclusive) upper value of the range
         inline label last() const;
 
-        //- Return true if the value is within the range
+        //- Reset start and size.
-        inline bool contains(const label) const;
+        //  Optionally adjust the start to avoid any negative indices.
+        //  Always reduce a negative size to zero.
+        //  Return true if the updated range valid (non-empty).
+        inline bool reset
+        (
+            const label start,
+            const label size,
+            const bool adjustStart = false
+        );
 
-        //- Return true if the ranges intersect
+        //- Return true if the value is within the range
+        inline bool contains(const label value) const;
+
+        //- Return true if the ranges overlap.
         //  Optional test for ranges that also just touch each other
-        bool intersects(const labelRange&, const bool touches = false) const;
+        bool overlaps(const labelRange& range, bool touches=false) const;
 
         //- Return a joined range, squashing any gaps in between
-        //  A prior intersects() check can be used to avoid squashing gaps.
+        //  A prior overlaps() check can be used to avoid squashing gaps.
-        labelRange join(const labelRange&) const;
+        labelRange join(const labelRange& range) const;
 
 
     // Member Operators
 
         //- Return element in range, no bounds checking
-        inline label operator[](const label) const;
+        inline label operator[](const label i) const;
 
-        //- Comparison function for sorting, compares the start
+        //- Comparison function for sorting, compares the start.
+        //  If the start values are equal, also compares the size.
         inline bool operator<(const labelRange& rhs) const;
 
         //- Join ranges, squashing any gaps in between
-        //  A prior intersects() check can be used to avoid squashing gaps.
+        //  A prior overlaps() check can be used to avoid squashing gaps.
-        labelRange& operator+=(const labelRange&);
+        void operator+=(const labelRange& rhs);
 
-        inline bool operator==(const labelRange&) const;
+        inline bool operator==(const labelRange& rhs) const;
-        inline bool operator!=(const labelRange&) const;
+        inline bool operator!=(const labelRange& rhs) const;
 
 
     // STL iterator
@@ -142,6 +173,8 @@ public:
         //- An STL const_iterator
         class const_iterator
         {
+            friend class labelRange;
+
             // Private data
 
                 //- Reference to the range for which this is an iterator
@@ -150,54 +183,48 @@ public:
                 //- Current index
                 label index_;
 
-        public:
 
             // Constructors
 
-                //- Construct null - equivalent to an 'end' position
+                //- Construct from range at 'begin' or 'end' position
-                inline const_iterator();
+                inline const_iterator
-
+                (
-                //- Construct from range, moving to its 'begin' position
+                    const labelRange& range,
-                inline explicit const_iterator(const labelRange&);
+                    const bool endIter = false
+                );
 
+        public:
 
             // Member operators
 
-                inline bool operator==(const const_iterator&) const;
+                inline bool operator==(const const_iterator& iter) const;
+                inline bool operator!=(const const_iterator& iter) const;
 
-                inline bool operator!=(const const_iterator&) const;
+                inline label operator*() const;
-
+                inline label operator()() const;
-                inline label operator*();
-                inline label operator()();
 
                 inline const_iterator& operator++();
                 inline const_iterator operator++(int);
         };
 
 
-        //- const_iterator set to the beginning of the range
+        //- A const_iterator set to the beginning of the range
         inline const_iterator cbegin() const;
 
-        //- const_iterator set to beyond the end of the range
+        //- A const_iterator set to beyond the end of the range
-        inline const const_iterator& cend() const;
+        inline const const_iterator cend() const;
 
-        //- const_iterator set to the beginning of the range
+        //- A const_iterator set to the beginning of the range
         inline const_iterator begin() const;
 
-        //- const_iterator set to beyond the end of the range
+        //- A const_iterator set to beyond the end of the range
-        inline const const_iterator& end() const;
+        inline const const_iterator end() const;
 
 
     // IOstream Operators
 
-        friend Istream& operator>>(Istream&, labelRange&);
+        friend Istream& operator>>(Istream& is, labelRange& range);
-        friend Ostream& operator<<(Ostream&, const labelRange&);
+        friend Ostream& operator<<(Ostream& os, const labelRange& range);
-
-
-private:
-
-        //- const_iterator returned by end(), cend()
-        static const const_iterator endIter_;
 
 };
 

src/OpenFOAM/primitives/ranges/labelRange/labelRangeI.H

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -33,32 +33,39 @@ inline Foam::labelRange::labelRange()
 {}
 
 
-inline Foam::labelRange::labelRange(const label start, const label size)
+inline Foam::labelRange::labelRange
+(
+    const label start,
+    const label size,
+    const bool adjustStart
+)
 :
     start_(start),
     size_(size)
 {
-    // disallow invalid sizes
+    if (adjustStart)
-    if (size_ <= 0)
     {
-        this->clear();
+        // Disallow invalid indices and sizes
+        adjust();
+    }
+    else if (size_ < 0)
+    {
+        // Disallow invalid sizes
+        size_ = 0;
     }
 }
 
 
 // * * * * * * * * * * * * * * * * Iterators * * * * * * * * * * * * * * * * //
 
-inline Foam::labelRange::const_iterator::const_iterator()
+inline Foam::labelRange::const_iterator::const_iterator
-:
+(
-   range_(*reinterpret_cast<Foam::labelRange* >(0)),
+    const labelRange& range,
-   index_(-1)
+    const bool endIter
-{}
+)
-
-
-inline Foam::labelRange::const_iterator::const_iterator(const labelRange& range)
 :
    range_(range),
-   index_(range_.empty() ? -1 : 0)
+   index_(endIter ? range_.size() : 0)
 {}
 
 
@@ -76,17 +83,17 @@ inline bool Foam::labelRange::const_iterator::operator!=
     const const_iterator& iter
 ) const
 {
-    return !(this->operator==(iter));
+    return (this->index_ != iter.index_);
 }
 
 
-inline Foam::label Foam::labelRange::const_iterator::operator*()
+inline Foam::label Foam::labelRange::const_iterator::operator*() const
 {
     return range_[index_];
 }
 
 
-inline Foam::label Foam::labelRange::const_iterator::operator()()
+inline Foam::label Foam::labelRange::const_iterator::operator()() const
 {
     return range_[index_];
 }
@@ -95,12 +102,7 @@ inline Foam::label Foam::labelRange::const_iterator::operator()()
 inline Foam::labelRange::const_iterator&
 Foam::labelRange::const_iterator::operator++()
 {
-    if (++index_ >= range_.size())
+    ++index_;
-    {
-        // equivalent to end iterator
-        index_ = -1;
-    }
-
     return *this;
 }
 
@@ -109,7 +111,7 @@ inline Foam::labelRange::const_iterator
 Foam::labelRange::const_iterator::operator++(int)
 {
     const_iterator old = *this;
-    this->operator++();
+    ++index_;
     return old;
 }
 
@@ -120,9 +122,9 @@ inline Foam::labelRange::const_iterator Foam::labelRange::cbegin() const
 }
 
 
-inline const Foam::labelRange::const_iterator& Foam::labelRange::cend() const
+inline const Foam::labelRange::const_iterator Foam::labelRange::cend() const
 {
-    return endIter_;
+    return const_iterator(*this, true);
 }
 
 
@@ -132,14 +134,31 @@ inline Foam::labelRange::const_iterator Foam::labelRange::begin() const
 }
 
 
-inline const Foam::labelRange::const_iterator& Foam::labelRange::end() const
+inline const Foam::labelRange::const_iterator Foam::labelRange::end() const
 {
-    return endIter_;
+    return const_iterator(*this, true);
 }
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
+inline void Foam::labelRange::resize(const label n)
+{
+    setSize(n);
+}
+
+
+inline void Foam::labelRange::setSize(const label n)
+{
+    size_ = n;
+
+    if (size_ < 0)
+    {
+        size_ = 0;
+    }
+}
+
+
 inline void Foam::labelRange::clear()
 {
     start_ = size_ = 0;
@@ -152,6 +171,12 @@ inline bool Foam::labelRange::empty() const
 }
 
 
+inline bool Foam::labelRange::valid() const
+{
+    return size_;
+}
+
+
 inline Foam::label Foam::labelRange::size() const
 {
     return size_;
@@ -170,6 +195,31 @@ inline Foam::label Foam::labelRange::last() const
 }
 
 
+inline bool Foam::labelRange::reset
+(
+    const label start,
+    const label size,
+    const bool adjustStart
+)
+{
+    start_ = start;
+    size_  = size;
+
+    if (adjustStart)
+    {
+        // Disallow invalid indices and sizes
+        adjust();
+    }
+    else if (size_ < 0)
+    {
+        // Disallow invalid sizes
+        size_ = 0;
+    }
+
+    return size_;
+}
+
+
 inline bool Foam::labelRange::contains(const label value) const
 {
     return value >= this->first() && value <= this->last();
@@ -186,7 +236,11 @@ inline Foam::label Foam::labelRange::operator[](const label i) const
 
 inline bool Foam::labelRange::operator<(const labelRange& rhs) const
 {
-    return this->first() < rhs.first();
+    return
+    (
+        this->first() < rhs.first()
+     || (this->first() == rhs.first() && this->size() < rhs.size())
+    );
 }
 
 

src/OpenFOAM/primitives/ranges/labelRange/labelRanges.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) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -26,11 +26,6 @@ License
 #include "labelRanges.H"
 #include "ListOps.H"
 
-// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
-
-const Foam::labelRanges::const_iterator Foam::labelRanges::endIter_;
-
-
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
 void Foam::labelRanges::insertBefore
@@ -141,7 +136,7 @@ bool Foam::labelRanges::add(const labelRange& range)
     {
         labelRange& currRange = ParentType::operator[](elemI);
 
-        if (currRange.intersects(range, true))
+        if (currRange.overlaps(range, true))
         {
             // absorb into the existing (adjacent/overlapping) range
             currRange += range;
@@ -150,7 +145,7 @@ bool Foam::labelRanges::add(const labelRange& range)
             for (; elemI < this->size()-1; ++elemI)
             {
                 labelRange& nextRange = ParentType::operator[](elemI+1);
-                if (currRange.intersects(nextRange, true))
+                if (currRange.overlaps(nextRange, true))
                 {
                     currRange += nextRange;
                     nextRange.clear();

src/OpenFOAM/primitives/ranges/labelRange/labelRanges.H

@@ -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) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -49,8 +49,8 @@ class Ostream;
 
 // Forward declaration of friend functions and operators
 class labelRanges;
-Istream& operator>>(Istream&, labelRanges&);
+Istream& operator>>(Istream& is, labelRanges& ranges);
-Ostream& operator<<(Ostream&, const labelRanges&);
+Ostream& operator<<(Ostream& is, const labelRanges& ranges);
 
 /*---------------------------------------------------------------------------*\
                          Class labelRanges Declaration
@@ -68,13 +68,13 @@ class labelRanges
     // Private Member Functions
 
         //- Insert range before specified insertion index, by copying up
-        void insertBefore(const label, const labelRange&);
+        void insertBefore(const label insert, const labelRange& range);
 
         //- Purge empty ranges, by copying down
         void purgeEmpty();
 
         //- Print the range for debugging purposes
-        Ostream& printRange(Ostream&, const labelRange&) const;
+        Ostream& printRange(Ostream& os, const labelRange& range) const;
 
 
 public:
@@ -85,10 +85,10 @@ public:
         inline labelRanges();
 
         //- Construct given size
-        inline explicit labelRanges(const label);
+        inline explicit labelRanges(const label nElem);
 
         //- Construct from Istream.
-        labelRanges(Istream&);
+        labelRanges(Istream& is);
 
 
     // Member Functions
@@ -100,19 +100,22 @@ public:
         using DynamicList<labelRange>::empty;
 
         //- Return true if the value is within any of the ranges
-        inline bool contains(const label) const;
+        inline bool contains(const label value) const;
 
         //- Add the range to the list
-        bool add(const labelRange&);
+        bool add(const labelRange& range);
 
         //- Remove the range from the list
-        bool remove(const labelRange&);
+        bool remove(const labelRange& range);
+
 
     // STL iterator
 
         //- An STL const_iterator
         class const_iterator
         {
+            friend class labelRanges;
+
             // Private data
 
                 //- Reference to the list for which this is an iterator
@@ -124,22 +127,21 @@ public:
                 //- Index of current element at listIndex
                 label subIndex_;
 
-        public:
-
             // Constructors
 
-                //- Construct null - equivalent to an 'end' position
+                //- Construct from ranges at 'begin' or 'end' position
-                inline const_iterator();
+                inline const_iterator
-
+                (
-                //- Construct from list, moving to its 'begin' position
+                    const labelRanges& lst,
-                inline explicit const_iterator(const labelRanges&);
+                    const bool endIter = false
+                );
 
+        public:
 
             // Member operators
 
-                inline bool operator==(const const_iterator&) const;
+                inline bool operator==(const const_iterator& iter) const;
-
+                inline bool operator!=(const const_iterator& iter) const;
-                inline bool operator!=(const const_iterator&) const;
 
                 inline label operator*();
                 inline label operator()();
@@ -149,29 +151,23 @@ public:
         };
 
 
-        //- const_iterator set to the beginning of the list
+        //- A const_iterator set to the beginning of the list
         inline const_iterator cbegin() const;
 
-        //- const_iterator set to beyond the end of the list
+        //- A const_iterator set to beyond the end of the list
-        inline const const_iterator& cend() const;
+        inline const const_iterator cend() const;
 
-        //- const_iterator set to the beginning of the list
+        //- A const_iterator set to the beginning of the list
         inline const_iterator begin() const;
 
-        //- const_iterator set to beyond the end of the list
+        //- A const_iterator set to beyond the end of the list
-        inline const const_iterator& end() const;
+        inline const const_iterator end() const;
 
 
     // IOstream Operators
 
-        friend Istream& operator>>(Istream&, labelRanges&);
+        friend Istream& operator>>(Istream& is, labelRanges& ranges);
-        friend Ostream& operator<<(Ostream&, const labelRanges&);
+        friend Ostream& operator<<(Ostream& os, const labelRanges& ranges);
-
-
-private:
-
-        //- const_iterator returned by end(), cend()
-        static const const_iterator endIter_;
 
 };
 

src/OpenFOAM/primitives/ranges/labelRange/labelRangesI.H

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2017 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -40,28 +40,18 @@ inline Foam::labelRanges::labelRanges(const label nElem)
 
 // * * * * * * * * * * * * * * * * Iterators * * * * * * * * * * * * * * * * //
 
-inline Foam::labelRanges::const_iterator::const_iterator()
+inline Foam::labelRanges::const_iterator::const_iterator
+(
+    const labelRanges& lst,
+    const bool endIter
+)
 :
-   list_(*reinterpret_cast<Foam::labelRanges* >(0)),
+    list_(lst),
-   index_(-1),
+    index_(endIter ? lst.size() : 0),
-   subIndex_(-1)
+    subIndex_(0)
 {}
 
 
-inline Foam::labelRanges::const_iterator::const_iterator(const labelRanges& lst)
-:
-   list_(lst),
-   index_(0),
-   subIndex_(0)
-{
-    if (list_.empty())
-    {
-        // equivalent to end iterator
-        index_ = subIndex_ = -1;
-    }
-}
-
-
 inline bool Foam::labelRanges::const_iterator::operator==
 (
     const const_iterator& iter
@@ -69,7 +59,7 @@ inline bool Foam::labelRanges::const_iterator::operator==
 {
     return
     (
-        this->index_ == iter.index_
+        this->index_    == iter.index_
      && this->subIndex_ == iter.subIndex_
     );
 }
@@ -101,13 +91,9 @@ Foam::labelRanges::const_iterator::operator++()
 {
     if (++subIndex_ >= list_[index_].size())
     {
-        // go to next list entry
+        // Next sub-list
+        ++index_;
         subIndex_ = 0;
-        if (++index_ >= list_.size())
-        {
-            // equivalent to end iterator
-            index_ = subIndex_ = -1;
-        }
     }
 
     return *this;
@@ -129,9 +115,9 @@ inline Foam::labelRanges::const_iterator Foam::labelRanges::cbegin() const
 }
 
 
-inline const Foam::labelRanges::const_iterator& Foam::labelRanges::cend() const
+inline const Foam::labelRanges::const_iterator Foam::labelRanges::cend() const
 {
-    return endIter_;
+    return const_iterator(*this, true);
 }
 
 
@@ -141,9 +127,9 @@ inline Foam::labelRanges::const_iterator Foam::labelRanges::begin() const
 }
 
 
-inline const Foam::labelRanges::const_iterator& Foam::labelRanges::end() const
+inline const Foam::labelRanges::const_iterator Foam::labelRanges::end() const
 {
-    return endIter_;
+    return const_iterator(*this, true);
 }