ENH: primitiveEntry construct with empty token list

- contents to be filled with a later assignment.

  This can help avoid deduction issues when populating from a list of
  tokens, and the templated version is selected:

  ```
  template<class T>
  primitiveEntry(const keyType&, const T&);
  ```

ENH: support construct empty ITstream with given name

- populate contents later by assigment

src/OpenFOAM/db/IOstreams/Tstreams/ITstream.C

@@ -425,7 +425,7 @@ void Foam::ITstream::append(token&& t, const bool lazy)
 }
 
 
-void Foam::ITstream::append(const tokenList& newTokens, const bool lazy)
+void Foam::ITstream::append(const UList<token>& newTokens, const bool lazy)
 {
     reserveCapacity(tokenIndex_ + newTokens.size(), lazy);
     tokenList& toks = *this;
@@ -438,7 +438,7 @@ void Foam::ITstream::append(const tokenList& newTokens, const bool lazy)
 }
 
 
-void Foam::ITstream::append(tokenList&& newTokens, const bool lazy)
+void Foam::ITstream::append(List<token>&& newTokens, const bool lazy)
 {
     reserveCapacity(tokenIndex_ + newTokens.size(), lazy);
     tokenList& toks = *this;
@@ -465,7 +465,7 @@ void Foam::ITstream::operator=(const ITstream& is)
 }
 
 
-void Foam::ITstream::operator=(const tokenList& toks)
+void Foam::ITstream::operator=(const UList<token>& toks)
 {
     tokenList::operator=(toks);
 
@@ -473,7 +473,7 @@ void Foam::ITstream::operator=(const tokenList& toks)
 }
 
 
-void Foam::ITstream::operator=(tokenList&& toks)
+void Foam::ITstream::operator=(List<token>&& toks)
 {
     tokenList::operator=(std::move(toks));
 

src/OpenFOAM/db/IOstreams/Tstreams/ITstream.H

@@ -99,6 +99,22 @@ public:
             setGood();
         }
 
+        //- Construct empty stream with given name
+        explicit ITstream
+        (
+            const string& name,
+            IOstreamOption streamOpt = IOstreamOption()
+        )
+        :
+            Istream(streamOpt),
+            tokenList(),
+            name_(name),
+            tokenIndex_(0)
+        {
+            setOpened();
+            setGood();
+        }
+
         //- Construct from components
         ITstream
         (
@@ -300,21 +316,21 @@ public:
             //- incrementing the index.
             void append(token&& t, const bool lazy);
 
-            //- Copy append a tokenList at the current tokenIndex,
+            //- Copy append a list of tokens at the current tokenIndex,
             //- incrementing the index.
             //
             //  \param newTokens the list of tokens to copy append
             //  \param lazy leaves any excess capacity for further appends.
             //      The caller will be responsible for resizing later.
-            void append(const tokenList& newTokens, const bool lazy);
+            void append(const UList<token>& newTokens, const bool lazy);
 
-            //- Move append a tokenList at the current tokenIndex,
+            //- Move append a list of tokens at the current tokenIndex,
             //- incrementing the index.
             //
             //  \param newTokens the list of tokens to move append
             //  \param lazy leaves any excess capacity for further appends.
             //      The caller will be responsible for resizing later.
-            void append(tokenList&& newTokens, const bool lazy);
+            void append(List<token>&& newTokens, const bool lazy);
 
             //- Set flags of stream
             ios_base::fmtflags flags(const ios_base::fmtflags)
@@ -339,10 +355,10 @@ public:
         void operator=(const ITstream& is);
 
         //- Copy assignment of tokens, with rewind()
-        void operator=(const tokenList& toks);
+        void operator=(const UList<token>& toks);
 
         //- Move assignment of tokens, with rewind()
-        void operator=(tokenList&& toks);
+        void operator=(List<token>&& toks);
 };
 
 

src/OpenFOAM/db/IOstreams/Tstreams/OTstream.H

@@ -80,12 +80,8 @@ public:
             versionNumber ver = currentVersion
         )
         :
-            Ostream(fmt, ver),
-            DynamicList<token>()
-        {
-            setOpened();
-            setGood();
-        }
+            OTstream(IOstreamOption(fmt, ver))
+        {}
 
         //- Copy construct
         OTstream(const OTstream& os)

src/OpenFOAM/db/dictionary/dictionary.H

@@ -187,7 +187,7 @@ public:
 
         public:
 
-            //- Construct null
+            //- Default construct
             Searcher()
             :
                 dict_(nullptr),
@@ -388,7 +388,7 @@ public:
 
     // Constructors
 
-        //- Construct top-level dictionary null
+        //- Default construct, a top-level empty dictionary
         dictionary();
 
         //- Construct top-level empty dictionary with given name

src/OpenFOAM/db/dictionary/primitiveEntry/primitiveEntry.C

@@ -213,13 +213,11 @@ bool Foam::primitiveEntry::expandVariable
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
-Foam::primitiveEntry::primitiveEntry(const keyType& key, const ITstream& is)
+Foam::primitiveEntry::primitiveEntry(const keyType& key)
 :
     entry(key),
-    ITstream(is)
-{
-    name() += '.' + keyword();
-}
+    ITstream(key, tokenList())
+{}
 
 
 Foam::primitiveEntry::primitiveEntry(const keyType& key, const token& tok)
@@ -251,6 +249,15 @@ Foam::primitiveEntry::primitiveEntry
 {}
 
 
+Foam::primitiveEntry::primitiveEntry(const keyType& key, const ITstream& is)
+:
+    entry(key),
+    ITstream(is)
+{
+    name() += '.' + key;
+}
+
+
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 Foam::label Foam::primitiveEntry::startLineNumber() const

src/OpenFOAM/db/dictionary/primitiveEntry/primitiveEntry.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017 OpenCFD Ltd.
+    Copyright (C) 2017-2020 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -54,6 +54,7 @@ SourceFiles
 namespace Foam
 {
 
+// Forward Declarations
 class dictionary;
 
 /*---------------------------------------------------------------------------*\
@@ -104,14 +105,9 @@ public:
 
     // Constructors
 
-        //- Construct from keyword and a Istream
-        primitiveEntry(const keyType& key, Istream& is);
-
-        //- Construct from keyword, parent dictionary and Istream
-        primitiveEntry(const keyType& key, const dictionary& dict, Istream& is);
-
-        //- Construct from keyword and a ITstream
-        primitiveEntry(const keyType& key, const ITstream& is);
+        //- Construct from keyword and no tokens.
+        //  Contents to be filled with a later assignment
+        explicit primitiveEntry(const keyType& key);
 
         //- Construct from keyword and a single token
         primitiveEntry(const keyType& key, const token& tok);
@@ -122,10 +118,20 @@ public:
         //- Construct from keyword and by transferring a list of tokens
         primitiveEntry(const keyType& key, List<token>&& tokens);
 
-        //- Construct from keyword and a T
+        //- Construct from keyword and ITstream tokens
+        primitiveEntry(const keyType& key, const ITstream& is);
+
+        //- Construct from keyword and Istream
+        primitiveEntry(const keyType& key, Istream& is);
+
+        //- Construct from keyword, parent dictionary and Istream
+        primitiveEntry(const keyType& key, const dictionary& dict, Istream& is);
+
+        //- Construct from keyword and a value. Uses string stream serialization
         template<class T>
         primitiveEntry(const keyType& key, const T& val);
 
+        //- Clone the entry
         autoPtr<entry> clone(const dictionary&) const
         {
             return autoPtr<entry>(new primitiveEntry(*this));