Inline variables

src/Compilers/Core/Portable/Collections/ImmutableArrayExtensions.cs

@@ -519,9 +519,7 @@ public static int Count<T>(this ImmutableArray<T> items, Func<T, bool> predicate
             {
                 var item = items[i];
                 var key = keySelector(item);
-
-                ArrayBuilder<T> bucket;
-                if (!accumulator.TryGetValue(key, out bucket))
+                if (!accumulator.TryGetValue(key, out var bucket))
                 {
                     bucket = ArrayBuilder<T>.GetInstance();
                     accumulator.Add(key, bucket);

src/Compilers/Core/Portable/Collections/OrderPreservingMultiDictionary.cs

@@ -88,8 +88,7 @@ private void EnsureDictionary()
         /// </summary>
         public void Add(K k, V v)
         {
-            ValueSet valueSet;
-            if (!this.IsEmpty && _dictionary.TryGetValue(k, out valueSet))
+            if (!this.IsEmpty && _dictionary.TryGetValue(k, out var valueSet))
             {
                 Debug.Assert(valueSet.Count >= 1);
                 // Have to re-store the ValueSet in case we upgraded the existing ValueSet from 
@@ -126,8 +125,7 @@ IEnumerator IEnumerable.GetEnumerator()
         {
             get
             {
-                ValueSet valueSet;
-                if (!this.IsEmpty && _dictionary.TryGetValue(k, out valueSet))
+                if (!this.IsEmpty && _dictionary.TryGetValue(k, out var valueSet))
                 {
                     Debug.Assert(valueSet.Count >= 1);
                     return valueSet.Items;
@@ -139,9 +137,8 @@ IEnumerator IEnumerable.GetEnumerator()
 
         public bool Contains(K key, V value)
         {
-            ValueSet valueSet;
             return !this.IsEmpty &&
-                _dictionary.TryGetValue(key, out valueSet) &&
+                _dictionary.TryGetValue(key, out var valueSet) &&
                 valueSet.Contains(value);
         }
 

src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerAssemblyLoader.cs

@@ -32,8 +32,7 @@ public void AddDependencyLocation(string fullPath)
 
             lock (_guard)
             {
-                List<string> paths;
-                if (!_knownAssemblyPathsBySimpleName.TryGetValue(simpleName, out paths))
+                if (!_knownAssemblyPathsBySimpleName.TryGetValue(simpleName, out var paths))
                 {
                     _knownAssemblyPathsBySimpleName.Add(simpleName, new List<string>() { fullPath });
                 }
@@ -65,8 +64,7 @@ private Assembly LoadFromPathUncheckedCore(string fullPath, AssemblyIdentity ide
             Assembly loadedAssembly = null;
             lock (_guard)
             {
-                Assembly existingAssembly;
-                if (_loadedAssembliesByPath.TryGetValue(fullPath, out existingAssembly))
+                if (_loadedAssembliesByPath.TryGetValue(fullPath, out var existingAssembly))
                 {
                     loadedAssembly = existingAssembly;
                 }
@@ -102,8 +100,7 @@ private Assembly AddToCache(Assembly assembly, string fullPath, AssemblyIdentity
             {
                 // The same assembly may be loaded from two different full paths (e.g. when loaded from GAC, etc.),
                 // or another thread might have loaded the assembly after we checked above.
-                Assembly existingAssembly;
-                if (_loadedAssembliesByIdentity.TryGetValue(identity, out existingAssembly))
+                if (_loadedAssembliesByIdentity.TryGetValue(identity, out var existingAssembly))
                 {
                     assembly = existingAssembly;
                 }
@@ -126,8 +123,7 @@ private AssemblyIdentity GetOrAddAssemblyIdentity(string fullPath)
 
             lock (_guard)
             {
-                AssemblyIdentity existingIdentity;
-                if (_loadedAssemblyIdentitiesByPath.TryGetValue(fullPath, out existingIdentity))
+                if (_loadedAssemblyIdentitiesByPath.TryGetValue(fullPath, out var existingIdentity))
                 {
                     return existingIdentity;
                 }
@@ -141,8 +137,7 @@ private AssemblyIdentity AddToCache(string fullPath, AssemblyIdentity identity)
         {
             lock (_guard)
             {
-                AssemblyIdentity existingIdentity;
-                if (_loadedAssemblyIdentitiesByPath.TryGetValue(fullPath, out existingIdentity) && existingIdentity != null)
+                if (_loadedAssemblyIdentitiesByPath.TryGetValue(fullPath, out var existingIdentity) && existingIdentity != null)
                 {
                     identity = existingIdentity;
                 }
@@ -157,8 +152,7 @@ private AssemblyIdentity AddToCache(string fullPath, AssemblyIdentity identity)
 
         public Assembly Load(string displayName)
         {
-            AssemblyIdentity requestedIdentity;
-            if (!AssemblyIdentity.TryParseDisplayName(displayName, out requestedIdentity))
+            if (!AssemblyIdentity.TryParseDisplayName(displayName, out var requestedIdentity))
             {
                 return null;
             }
@@ -166,17 +160,14 @@ public Assembly Load(string displayName)
             ImmutableArray<string> candidatePaths;
             lock (_guard)
             {
-                Assembly existingAssembly;
-                
+
                 // First, check if this loader already loaded the requested assembly:
-                if (_loadedAssembliesByIdentity.TryGetValue(requestedIdentity, out existingAssembly))
+                if (_loadedAssembliesByIdentity.TryGetValue(requestedIdentity, out var existingAssembly))
                 {
                     return existingAssembly;
                 }
-
                 // Second, check if an assembly file of the same simple name was registered with the loader:
-                List<string> pathList;
-                if (!_knownAssemblyPathsBySimpleName.TryGetValue(requestedIdentity.Name, out pathList))
+                if (!_knownAssemblyPathsBySimpleName.TryGetValue(requestedIdentity.Name, out var pathList))
                 {
                     return null;
                 }

src/Compilers/Core/Portable/InternalUtilities/ConcurrentSet.cs

@@ -106,8 +106,7 @@ public void AddRange(IEnumerable<T> values)
         /// <returns>true if the value was removed successfully; otherwise false.</returns>
         public bool Remove(T value)
         {
-            byte b;
-            return _dictionary.TryRemove(value, out b);
+            return _dictionary.TryRemove(value, out var b);
         }
 
         /// <summary>

src/Compilers/Core/Portable/InternalUtilities/MultiDictionary.cs

@@ -186,8 +186,7 @@ public IEnumerable<K> Keys
         {
             get
             {
-                ValueSet set;
-                return _dictionary.TryGetValue(k, out set) ? set : default(ValueSet);
+                return _dictionary.TryGetValue(k, out var set) ? set : default(ValueSet);
             }
         }
 
@@ -208,8 +207,7 @@ public MultiDictionary(int capacity, IEqualityComparer<K> comparer)
 
         public void Add(K k, V v)
         {
-            ValueSet set;
-            _dictionary[k] = _dictionary.TryGetValue(k, out set) ? set.Add(v) : new ValueSet(v);
+            _dictionary[k] = _dictionary.TryGetValue(k, out var set) ? set.Add(v) : new ValueSet(v);
         }
 
         IEnumerator IEnumerable.GetEnumerator()

src/Compilers/Core/Portable/InternalUtilities/StringExtensions.cs

@@ -142,8 +142,7 @@ internal static bool IsValidClrNamespaceName(this string name)
             this string name,
             bool isCaseSensitive)
         {
-            string result;
-            return TryGetWithoutAttributeSuffix(name, isCaseSensitive, out result) ? result : null;
+            return TryGetWithoutAttributeSuffix(name, isCaseSensitive, out var result) ? result : null;
         }
 
         internal static bool TryGetWithoutAttributeSuffix(
@@ -198,8 +197,7 @@ internal static bool IsValidUnicodeString(this string str)
         /// </summary>
         internal static string Unquote(this string arg)
         {
-            bool quoted;
-            return Unquote(arg, out quoted);
+            return Unquote(arg, out var quoted);
         }
 
         internal static string Unquote(this string arg, out bool quoted)

src/Compilers/Core/Portable/InternalUtilities/WeakReferenceExtensions.cs

@@ -9,15 +9,13 @@ internal static class WeakReferenceExtensions
     {
         public static T GetTarget<T>(this WeakReference<T> reference) where T : class
         {
-            T target;
-            reference.TryGetTarget(out target);
+            reference.TryGetTarget(out var target);
             return target;
         }
 
         public static bool IsNull<T>(this WeakReference<T> reference) where T : class
         {
-            T target;
-            return !reference.TryGetTarget(out target);
+            return !reference.TryGetTarget(out var target);
         }
     }
 }

src/Compilers/Core/Portable/Serialization/FixedObjectBinder.cs

@@ -22,15 +22,13 @@ public FixedObjectBinder(ImmutableDictionary<Type, Func<ObjectReader, object>> r
 
         public override Type GetType(string assemblyName, string typeName)
         {
-            Type type;
-            _typeMap.TryGetValue(new TypeKey(assemblyName, typeName), out type);
+            _typeMap.TryGetValue(new TypeKey(assemblyName, typeName), out var type);
             return type;
         }
 
         public override Func<ObjectReader, object> GetReader(Type type)
         {
-            Func<ObjectReader, object> reader;
-            _readerMap.TryGetValue(type, out reader);
+            _readerMap.TryGetValue(type, out var reader);
             return reader;
         }
     }

src/Compilers/Core/Portable/Serialization/ObjectReader.cs

@@ -335,10 +335,8 @@ private Array ReadArray(DataKind kind)
             }
 
             var elementKind = (DataKind)_reader.ReadByte();
-
             // optimization for primitive type array
-            Type elementType;
-            if (s_reverseTypeMap.TryGetValue(elementKind, out elementType))
+            if (s_reverseTypeMap.TryGetValue(elementKind, out var elementType))
             {
                 return this.ReadPrimitiveTypeArrayElements(elementType, elementKind, length);
             }

src/Compilers/Core/Portable/Serialization/ObjectWriter.cs

@@ -214,8 +214,7 @@ public unsafe void WriteString(string value)
             }
             else
             {
-                int id;
-                if (_dataMap.TryGetId(value, out id))
+                if (_dataMap.TryGetId(value, out var id))
                 {
                     Debug.Assert(id >= 0);
                     if (id <= byte.MaxValue)
@@ -474,10 +473,8 @@ private void WriteArray(Array instance)
 
             // get type of array
             var elementType = instance.GetType().GetElementType();
-
             // optimization for primitive type array
-            DataKind elementKind;
-            if (s_typeMap.TryGetValue(elementType, out elementKind))
+            if (s_typeMap.TryGetValue(elementType, out var elementKind))
             {
                 this.WritePrimitiveType(elementType, elementKind);
                 this.WritePrimitiveTypeArrayElements(elementType, elementKind, instance);
@@ -595,8 +592,7 @@ private void WritePrimitiveType(Type type, DataKind kind)
 
         private void WriteType(Type type)
         {
-            int id;
-            if (_dataMap.TryGetId(type, out id))
+            if (_dataMap.TryGetId(type, out var id))
             {
                 Debug.Assert(id >= 0);
                 if (id <= byte.MaxValue)
@@ -637,10 +633,8 @@ private void WriteType(Type type)
         private void WriteObject(object instance)
         {
             _cancellationToken.ThrowIfCancellationRequested();
-
             // write object ref if we already know this instance
-            int id;
-            if (_dataMap.TryGetId(instance, out id))
+            if (_dataMap.TryGetId(instance, out var id))
             {
                 Debug.Assert(id >= 0);
                 if (id <= byte.MaxValue)

src/Compilers/Core/Portable/Serialization/SimpleRecordingObjectBinder.cs

@@ -20,8 +20,7 @@ internal sealed class SimpleRecordingObjectBinder : RecordingObjectBinder
 
         public override Type GetType(string assemblyName, string typeName)
         {
-            Type type;
-            if (!_typeMap.TryGetValue(new TypeKey(assemblyName, typeName), out type))
+            if (!_typeMap.TryGetValue(new TypeKey(assemblyName, typeName), out var type))
             {
                 Debug.Assert(false, assemblyName + "/" + typeName + " don't exist");
             }
@@ -31,8 +30,7 @@ public override Type GetType(string assemblyName, string typeName)
 
         public override Func<ObjectReader, object> GetReader(Type type)
         {
-            Func<ObjectReader, object> reader;
-            if (!_readerMap.TryGetValue(type, out reader))
+            if (!_readerMap.TryGetValue(type, out var reader))
             {
                 Debug.Assert(false, type.ToString() + " reader doesn't exist");
             }

src/Dependencies/PooledObjects/ArrayBuilder.cs

@@ -402,9 +402,7 @@ System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
             {
                 var item = this[i];
                 var key = keySelector(item);
-
-                ArrayBuilder<T> bucket;
-                if (!accumulator.TryGetValue(key, out bucket))
+                if (!accumulator.TryGetValue(key, out var bucket))
                 {
                     bucket = ArrayBuilder<T>.GetInstance();
                     accumulator.Add(key, bucket);

src/Workspaces/Core/Portable/CodeCleanup/Providers/FormatCodeCleanupProvider.cs

@@ -18,8 +18,7 @@ public string Name
         public async Task<Document> CleanupAsync(Document document, IEnumerable<TextSpan> spans, CancellationToken cancellationToken)
         {
             // If the old text already exists, use the fast path for formatting.
-            SourceText oldText;
-            if (document.TryGetText(out oldText))
+            if (document.TryGetText(out var oldText))
             {
                 var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
                 var textChanges = await Formatter.GetFormattedTextChangesAsync(root, spans, document.Project.Solution.Workspace, cancellationToken: cancellationToken).ConfigureAwait(false);
@@ -38,8 +37,7 @@ public async Task<Document> CleanupAsync(Document document, IEnumerable<TextSpan
         public async Task<SyntaxNode> CleanupAsync(SyntaxNode root, IEnumerable<TextSpan> spans, Workspace workspace, CancellationToken cancellationToken)
         {
             // If the old text already exists, use the fast path for formatting.
-            SourceText oldText;
-            if (root.SyntaxTree != null && root.SyntaxTree.TryGetText(out oldText))
+            if (root.SyntaxTree != null && root.SyntaxTree.TryGetText(out var oldText))
             {
                 var changes = await Formatter.GetFormattedTextChangesAsync(root, spans, workspace, cancellationToken: cancellationToken).ConfigureAwait(false);
 

src/Workspaces/Core/Portable/CodeFixes/FixAllOccurrences/BatchFixAllProvider.cs

@@ -238,9 +238,7 @@ public virtual string GetFixAllTitle(FixAllState fixAllState)
                 {
                     cancellationToken.ThrowIfCancellationRequested();
                     var document = changedSolution.GetDocument(documentId);
-
-                    Document existingDocument;
-                    if (changedDocumentsMap.TryGetValue(documentId, out existingDocument))
+                    if (changedDocumentsMap.TryGetValue(documentId, out var existingDocument))
                     {
                         if (existingDocument != null)
                         {

src/Workspaces/Core/Portable/Execution/AssetStorages.Storage.cs

@@ -216,8 +216,7 @@ public void Append(HashSet<Checksum> searchingChecksumsLeft, Dictionary<Checksum
             private void Append(HashSet<Checksum> searchingChecksumsLeft, Dictionary<Checksum, object> result)
             {
                 // only solution with checksum can be in asset storage
-                SolutionStateChecksums stateChecksums;
-                Contract.ThrowIfFalse(_state.TryGetStateChecksums(out stateChecksums));
+                Contract.ThrowIfFalse(_state.TryGetStateChecksums(out var stateChecksums));
 
                 stateChecksums.Find(_state, searchingChecksumsLeft, result, _cancellationToken);
             }

src/Workspaces/Core/Portable/FindSymbols/Extensions.cs

@@ -17,8 +17,7 @@ internal static partial class Extensions
         public static async Task<IEnumerable<SyntaxToken>> GetConstructorInitializerTokensAsync(this Document document, CancellationToken cancellationToken)
         {
             // model should exist already
-            SemanticModel model;
-            if (!document.TryGetSemanticModel(out model))
+            if (!document.TryGetSemanticModel(out var model))
             {
                 return Contract.FailWithReturn<IEnumerable<SyntaxToken>>("we should never reach here");
             }
@@ -38,8 +37,7 @@ public static async Task<IEnumerable<SyntaxToken>> GetConstructorInitializerToke
             this Document document, string identifier, CancellationToken cancellationToken)
         {
             // model should exist already
-            SemanticModel model;
-            if (!document.TryGetSemanticModel(out model))
+            if (!document.TryGetSemanticModel(out var model))
             {
                 return Contract.FailWithReturn<ImmutableArray<SyntaxToken>>("we should never reach here");
             }

src/Workspaces/Core/Portable/FindSymbols/SymbolFinder.cs

@@ -134,12 +134,11 @@ public static partial class SymbolFinder
                 // then we have a retargeting scenario and want to take our usual path below as if it was a metadata reference
                 foreach (var sourceProject in solution.Projects)
                 {
-                    Compilation compilation;
 
                     // If our symbol is actually a "regular" source symbol, then we know the compilation is holding the symbol alive
                     // and thus TryGetCompilation is sufficient. For another example of this pattern, see Solution.GetProject(IAssemblySymbol)
                     // which we happen to call below.
-                    if (sourceProject.TryGetCompilation(out compilation))
+                    if (sourceProject.TryGetCompilation(out var compilation))
                     {
                         if (symbol.ContainingAssembly.Equals(compilation.Assembly))
                         {

src/Workspaces/Core/Portable/Formatting/Engine/TreeData.cs

@@ -16,8 +16,7 @@ internal abstract partial class TreeData
         public static TreeData Create(SyntaxNode root)
         {
             // either there is no tree or a tree that is not generated from a text.
-            var text = default(SourceText);
-            if (root.SyntaxTree == null || !root.SyntaxTree.TryGetText(out text))
+            if (root.SyntaxTree == null || !root.SyntaxTree.TryGetText(out var text))
             {
                 return new Node(root);
             }

src/Workspaces/Core/Portable/PatternMatching/PatternMatcher.cs

@@ -260,8 +260,7 @@ public PatternMatches GetMatches(string candidate, string dottedContainer)
                 return null;
             }
 
-            ImmutableArray<PatternMatch> ignored;
-            return MatchSegment(candidate, inludeMatchSpans, _fullPatternSegment, wantAllMatches: false, allMatches: out ignored, fuzzyMatch: false) ??
+            return MatchSegment(candidate, inludeMatchSpans, _fullPatternSegment, wantAllMatches: false, allMatches: out var ignored, fuzzyMatch: false) ??
                    MatchSegment(candidate, inludeMatchSpans, _fullPatternSegment, wantAllMatches: false, allMatches: out ignored, fuzzyMatch: true);
         }
 
@@ -451,9 +450,8 @@ private static bool ContainsSpaceOrAsterisk(string text)
                 return ImmutableArray<PatternMatch>.Empty;
             }
 
-            ImmutableArray<PatternMatch> matches;
             var singleMatch = MatchSegment(candidate, includeMatchSpans, segment, 
-                wantAllMatches: true, fuzzyMatch: fuzzyMatch, allMatches: out matches);
+                wantAllMatches: true, fuzzyMatch: fuzzyMatch, allMatches: out var matches);
             if (singleMatch.HasValue)
             {
                 return ImmutableArray.Create(singleMatch.Value);

src/Workspaces/Core/Portable/Rename/ConflictEngine/ConflictResolver.cs

@@ -263,8 +263,7 @@ private static void AddConflictingSymbolLocations(IEnumerable<ISymbol> conflicti
                 {
                     if (newLocation.IsInSource)
                     {
-                        Location oldLocation;
-                        if (reverseMappedLocations.TryGetValue(newLocation, out oldLocation))
+                        if (reverseMappedLocations.TryGetValue(newLocation, out var oldLocation))
                         {
                             conflictResolution.AddOrReplaceRelatedLocation(new RelatedLocation(oldLocation.SourceSpan, conflictResolution.OldSolution.GetDocument(oldLocation.SourceTree).Id, RelatedLocationType.UnresolvableConflict));
                         }

src/Workspaces/Core/Portable/Rename/ConflictEngine/DeclarationConflictHelpers.cs

@@ -30,9 +30,7 @@ public static IEnumerable<Location> GetMembersWithConflictingSignatures(IMethodS
 
             foreach (var signature in GetAllSignatures(renamedMethod, trimOptionalParameters))
             {
-                IMethodSymbol conflictingSymbol;
-
-                if (signatureToConflictingMember.TryGetValue(signature, out conflictingSymbol))
+                if (signatureToConflictingMember.TryGetValue(signature, out var conflictingSymbol))
                 {
                     if (!(conflictingSymbol.PartialDefinitionPart != null && conflictingSymbol.PartialDefinitionPart == renamedMethod) &&
                         !(conflictingSymbol.PartialImplementationPart != null && conflictingSymbol.PartialImplementationPart == renamedMethod))

src/Workspaces/Core/Portable/Rename/ConflictEngine/RenamedSpansTracker.cs

@@ -33,8 +33,7 @@ internal bool IsDocumentChanged(DocumentId documentId)
 
         internal void AddModifiedSpan(DocumentId documentId, TextSpan oldSpan, TextSpan newSpan)
         {
-            List<(TextSpan oldSpan, TextSpan newSpan)> spans;
-            if (!_documentToModifiedSpansMap.TryGetValue(documentId, out spans))
+            if (!_documentToModifiedSpansMap.TryGetValue(documentId, out var spans))
             {
                 spans = new List<(TextSpan oldSpan, TextSpan newSpan)>();
                 _documentToModifiedSpansMap[documentId] = spans;
@@ -45,8 +44,7 @@ internal void AddModifiedSpan(DocumentId documentId, TextSpan oldSpan, TextSpan
 
         internal void AddComplexifiedSpan(DocumentId documentId, TextSpan oldSpan, TextSpan newSpan, List<(TextSpan oldSpan, TextSpan newSpan)> modifiedSubSpans)
         {
-            List<ComplexifiedSpan> spans;
-            if (!_documentToComplexifiedSpansMap.TryGetValue(documentId, out spans))
+            if (!_documentToComplexifiedSpansMap.TryGetValue(documentId, out var spans))
             {
                 spans = new List<ComplexifiedSpan>();
                 _documentToComplexifiedSpansMap[documentId] = spans;
@@ -57,8 +55,7 @@ internal void AddComplexifiedSpan(DocumentId documentId, TextSpan oldSpan, TextS
 
         internal TextSpan GetAdjustedComplexifiedSpan(TextSpan originalComplexifiedSpan, DocumentId documentId)
         {
-            List<ComplexifiedSpan> complexifiedSpans;
-            if (!_documentToComplexifiedSpansMap.TryGetValue(documentId, out complexifiedSpans))
+            if (!_documentToComplexifiedSpansMap.TryGetValue(documentId, out var complexifiedSpans))
             {
                 throw new ArgumentException("documentId");
             }

src/Workspaces/Core/Portable/Shared/Extensions/DocumentExtensions.cs

@@ -178,9 +178,7 @@ public static Task<SyntaxTreeIndex> GetSyntaxTreeIndexAsync(this Document docume
         /// </summary>
         public static async Task<SemanticModel> GetPartialSemanticModelAsync(this Document document, CancellationToken cancellationToken)
         {
-            Compilation compilation;
-
-            if (document.Project.TryGetCompilation(out compilation))
+            if (document.Project.TryGetCompilation(out var compilation))
             {
                 // We already have a compilation, so at this point it's fastest to just get a SemanticModel
                 return await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);

src/Workspaces/Core/Portable/Utilities/CancellableLazy`1.cs

@@ -26,8 +26,7 @@ public bool HasValue
         {
             get
             {
-                T tmp;
-                return this.TryGetValue(out tmp);
+                return this.TryGetValue(out var tmp);
             }
         }
 

src/Workspaces/Core/Portable/Utilities/CompilerUtilities/linkedhashqueue.cs

@@ -60,9 +60,7 @@ public T First
         public bool Enqueue(T value)
         {
             var result = true;
-
-            LinkedListNode<T> node;
-            if (_map.TryGetValue(value, out node))
+            if (_map.TryGetValue(value, out var node))
             {
                 // Already had this in the list.  Return 'false'.  
                 result = false;
@@ -92,14 +90,12 @@ public T Dequeue()
 
         public bool Contains(T value)
         {
-            LinkedListNode<T> node;
-            return _map.TryGetValue(value, out node);
+            return _map.TryGetValue(value, out var node);
         }
 
         public void Remove(T value)
         {
-            LinkedListNode<T> node;
-            _map.TryGetValue(value, out node);
+            _map.TryGetValue(value, out var node);
             if (_map.Remove(value))
             {
                 _list.Remove(node);

src/Workspaces/Core/Portable/Utilities/Documentation/XmlDocumentationProvider.cs

@@ -90,8 +90,7 @@ protected override string GetDocumentationForSymbol(string documentationMemberID
                 }
             }
 
-            string docComment;
-            return _docComments.TryGetValue(documentationMemberID, out docComment) ? docComment : "";
+            return _docComments.TryGetValue(documentationMemberID, out var docComment) ? docComment : "";
         }
 
         private static readonly XmlReaderSettings s_xmlSettings = new XmlReaderSettings()

src/Workspaces/Core/Portable/Utilities/SpellChecker.cs

@@ -127,8 +127,7 @@ public static bool AreSimilar(string originalText, string candidateText)
 
         public static bool AreSimilar(string originalText, string candidateText, bool substringsAreSimilar)
         {
-            double unused;
-            return AreSimilar(originalText, candidateText, substringsAreSimilar, out unused);
+            return AreSimilar(originalText, candidateText, substringsAreSimilar, out var unused);
         }
 
         public static bool AreSimilar(string originalText, string candidateText, out double similarityWeight)
@@ -158,8 +157,7 @@ internal static int GetThreshold(string value)
 
         public bool AreSimilar(string candidateText)
         {
-            double similarityWeight;
-            return AreSimilar(candidateText, out similarityWeight);
+            return AreSimilar(candidateText, out var similarityWeight);
         }
 
         public bool AreSimilar(string candidateText, out double similarityWeight)

src/Workspaces/Core/Portable/Utilities/SyntaxPath.cs

@@ -138,8 +138,7 @@ public bool TryResolve<TNode>(SyntaxTree syntaxTree, CancellationToken cancellat
         public bool TryResolve<TNode>(SyntaxNode root, out TNode node)
             where TNode : SyntaxNode
         {
-            SyntaxNodeOrToken nodeOrToken;
-            if (TryResolve(root, out nodeOrToken) &&
+            if (TryResolve(root, out var nodeOrToken) &&
                 nodeOrToken.IsNode &&
                 nodeOrToken.AsNode() is TNode)
             {

src/Workspaces/Core/Portable/Utilities/ValuesSources/CachedWeakValueSource.cs

@@ -36,8 +36,7 @@ public override bool TryGetValue(out T value)
 
         public override T GetValue(CancellationToken cancellationToken = default(CancellationToken))
         {
-            T value;
-            if (!_reference.TryGetTarget(out value))
+            if (!_reference.TryGetTarget(out var value))
             {
                 using (Gate.DisposableWait(cancellationToken))
                 {
@@ -54,8 +53,7 @@ public override T GetValue(CancellationToken cancellationToken = default(Cancell
 
         public override async Task<T> GetValueAsync(CancellationToken cancellationToken = default(CancellationToken))
         {
-            T value;
-            if (!_reference.TryGetTarget(out value))
+            if (!_reference.TryGetTarget(out var value))
             {
                 using (await Gate.DisposableWaitAsync(cancellationToken).ConfigureAwait(false))
                 {

src/Workspaces/Core/Portable/Utilities/ValuesSources/RecoverableWeakValueSource.cs

@@ -71,9 +71,7 @@ public override bool TryGetValue(out T value)
         public override T GetValue(CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            T instance;
-            if (!_weakInstance.TryGetTarget(out instance))
+            if (!_weakInstance.TryGetTarget(out var instance))
             {
                 Task saveTask = null;
                 using (this.Gate.DisposableWait(cancellationToken))
@@ -93,8 +91,7 @@ public override T GetValue(CancellationToken cancellationToken)
 
         public override async Task<T> GetValueAsync(CancellationToken cancellationToken)
         {
-            T instance;
-            if (!_weakInstance.TryGetTarget(out instance))
+            if (!_weakInstance.TryGetTarget(out var instance))
             {
                 Task saveTask = null;
                 using (await this.Gate.DisposableWaitAsync(cancellationToken).ConfigureAwait(false))

src/Workspaces/Core/Portable/Utilities/ValuesSources/ValueSource.cs

@@ -18,8 +18,7 @@ public bool HasValue
         {
             get
             {
-                T tmp;
-                return this.TryGetValue(out tmp);
+                return this.TryGetValue(out var tmp);
             }
         }
 

src/Workspaces/Core/Portable/Utilities/ValuesSources/WeakConstantValueSource.cs

@@ -22,8 +22,7 @@ public override T GetValue(CancellationToken cancellationToken)
         {
             if (_weakValue != null)
             {
-                T value;
-                if (_weakValue.TryGetTarget(out value))
+                if (_weakValue.TryGetTarget(out var value))
                 {
                     return value;
                 }

src/Workspaces/Core/Portable/Utilities/WeakEventHandler.cs

@@ -19,8 +19,7 @@ public static EventHandler<TArgs> Create<TTarget>(TTarget target, Action<TTarget
 
             return (sender, args) =>
             {
-                TTarget targ;
-                if (weakTarget.TryGetTarget(out targ))
+                if (weakTarget.TryGetTarget(out var targ))
                 {
                     invoker(targ, sender, args);
                 }

src/Workspaces/Core/Portable/Workspace/Host/Mef/MefLanguageServices.cs

@@ -48,8 +48,7 @@ public bool HasServices
 
         public override TLanguageService GetService<TLanguageService>()
         {
-            Lazy<ILanguageService, LanguageServiceMetadata> service;
-            if (TryGetService(typeof(TLanguageService), out service))
+            if (TryGetService(typeof(TLanguageService), out var service))
             {
                 return (TLanguageService)service.Value;
             }
@@ -76,10 +75,9 @@ internal bool TryGetService(Type serviceType, out Lazy<ILanguageService, Languag
 
         private Lazy<ILanguageService, LanguageServiceMetadata> PickLanguageService(IEnumerable<Lazy<ILanguageService, LanguageServiceMetadata>> services)
         {
-            Lazy<ILanguageService, LanguageServiceMetadata> service;
 
             // workspace specific kind is best
-            if (TryGetServiceByLayer(_workspaceServices.Workspace.Kind, services, out service))
+            if (TryGetServiceByLayer(_workspaceServices.Workspace.Kind, services, out var service))
             {
                 return service;
             }

src/Workspaces/Core/Portable/Workspace/Host/Mef/MefWorkspaceServices.cs

@@ -50,8 +50,7 @@ public override Workspace Workspace
 
         public override TWorkspaceService GetService<TWorkspaceService>()
         {
-            Lazy<IWorkspaceService, WorkspaceServiceMetadata> service;
-            if (TryGetService(typeof(TWorkspaceService), out service))
+            if (TryGetService(typeof(TWorkspaceService), out var service))
             {
                 return (TWorkspaceService)service.Value;
             }
@@ -79,10 +78,9 @@ private bool TryGetService(Type serviceType, out Lazy<IWorkspaceService, Workspa
 
         private Lazy<IWorkspaceService, WorkspaceServiceMetadata> PickWorkspaceService(IEnumerable<Lazy<IWorkspaceService, WorkspaceServiceMetadata>> services)
         {
-            Lazy<IWorkspaceService, WorkspaceServiceMetadata> service;
 
             // workspace specific kind is best
-            if (TryGetServiceByLayer(_workspace.Kind, services, out service))
+            if (TryGetServiceByLayer(_workspace.Kind, services, out var service))
             {
                 return service;
             }
@@ -151,9 +149,7 @@ public override bool IsSupported(string languageName)
         public override HostLanguageServices GetLanguageServices(string languageName)
         {
             var currentServicesMap = _languageServicesMap;
-
-            MefLanguageServices languageServices;
-            if (!currentServicesMap.TryGetValue(languageName, out languageServices))
+            if (!currentServicesMap.TryGetValue(languageName, out var languageServices))
             {
                 languageServices = ImmutableInterlocked.GetOrAdd(ref _languageServicesMap, languageName, _ => new MefLanguageServices(this, languageName));
             }
@@ -174,9 +170,7 @@ public override IEnumerable<TLanguageService> FindLanguageServices<TLanguageServ
             foreach (var language in this.SupportedLanguages)
             {
                 var services = (MefLanguageServices)this.GetLanguageServices(language);
-
-                Lazy<ILanguageService, LanguageServiceMetadata> service;
-                if (services.TryGetService(typeof(TLanguageService), out service))
+                if (services.TryGetService(typeof(TLanguageService), out var service))
                 {
                     if (filter(service.Metadata.Data))
                     {

src/Workspaces/Core/Portable/Workspace/Host/Metadata/MetadataReferenceCache.cs

@@ -24,8 +24,7 @@ public MetadataReferenceCache(Func<string, MetadataReferenceProperties, Metadata
 
         public MetadataReference GetReference(string path, MetadataReferenceProperties properties)
         {
-            ReferenceSet referenceSet;
-            if (!_referenceSets.TryGetValue(path, out referenceSet))
+            if (!_referenceSets.TryGetValue(path, out var referenceSet))
             {
                 referenceSet = ImmutableInterlocked.GetOrAdd(ref _referenceSets, path, new ReferenceSet(this));
             }
@@ -55,10 +54,8 @@ public MetadataReference GetAddOrUpdate(string path, MetadataReferenceProperties
             {
                 using (_gate.DisposableWait())
                 {
-                    WeakReference<MetadataReference> weakref;
                     MetadataReference mref = null;
-
-                    if (!(_references.TryGetValue(properties, out weakref) && weakref.TryGetTarget(out mref)))
+                    if (!(_references.TryGetValue(properties, out var weakref) && weakref.TryGetTarget(out mref)))
                     {
                         // try to base this metadata reference off of an existing one, so we don't load the metadata bytes twice.
                         foreach (var wr in _references.Values)

src/Workspaces/Core/Portable/Workspace/Host/SyntaxTreeFactory/AbstractSyntaxTreeFactoryService.AbstractRecoverableSyntaxRoot.cs

@@ -30,8 +30,7 @@ public SyntaxTreeInfo(string filePath, ParseOptions options, ValueSource<TextAnd
 
             internal bool TryGetText(out SourceText text)
             {
-                TextAndVersion textAndVersion;
-                if (this.TextSource.TryGetValue(out textAndVersion))
+                if (this.TextSource.TryGetValue(out var textAndVersion))
                 {
                     text = textAndVersion.Text;
                     return true;
@@ -90,8 +89,7 @@ internal sealed class RecoverableSyntaxRoot<TRoot> : RecoverableWeakValueSource<
 
             public RecoverableSyntaxRoot<TRoot> WithSyntaxTree(IRecoverableSyntaxTree<TRoot> containingTree)
             {
-                TRoot root;
-                if (this.TryGetValue(out root))
+                if (this.TryGetValue(out var root))
                 {
                     var result = new RecoverableSyntaxRoot<TRoot>(_service, root, containingTree);
                     result._storage = _storage;

src/Workspaces/Core/Portable/Workspace/Solution/Document.cs

@@ -80,9 +80,7 @@ public bool TryGetSyntaxTree(out SyntaxTree syntaxTree)
         public bool TryGetSyntaxVersion(out VersionStamp version)
         {
             version = default(VersionStamp);
-
-            VersionStamp textVersion;
-            if (!this.TryGetTextVersion(out textVersion))
+            if (!this.TryGetTextVersion(out var textVersion))
             {
                 return false;
             }
@@ -155,10 +153,8 @@ public Task<SyntaxTree> GetSyntaxTreeAsync(CancellationToken cancellationToken =
             {
                 return _syntaxTreeResultTask;
             }
-
             // check to see if we already have the tree before actually going async
-            SyntaxTree tree;
-            if (TryGetSyntaxTree(out tree))
+            if (TryGetSyntaxTree(out var tree))
             {
                 // stash a completed result task for this value for the next request (to reduce extraneous allocations of tasks)
                 // don't use the actual async task because it depends on a specific cancellation token
@@ -189,8 +185,7 @@ internal SyntaxTree GetSyntaxTreeSynchronously(CancellationToken cancellationTok
         public bool TryGetSyntaxRoot(out SyntaxNode root)
         {
             root = null;
-            SyntaxTree tree;
-            return this.TryGetSyntaxTree(out tree) && tree.TryGetRoot(out root) && root != null;
+            return this.TryGetSyntaxTree(out var tree) && tree.TryGetRoot(out root) && root != null;
         }
 
         /// <summary>
@@ -246,8 +241,7 @@ public async Task<SemanticModel> GetSemanticModelAsync(CancellationToken cancell
                     return null;
                 }
 
-                SemanticModel semanticModel;
-                if (this.TryGetSemanticModel(out semanticModel))
+                if (this.TryGetSemanticModel(out var semanticModel))
                 {
                     return semanticModel;
                 }
@@ -330,10 +324,7 @@ public async Task<IEnumerable<TextChange>> GetTextChangesAsync(Document oldDocum
 
                     // first try to see if text already knows its changes
                     IList<TextChange> textChanges = null;
-
-                    SourceText text;
-                    SourceText oldText;
-                    if (this.TryGetText(out text) && oldDocument.TryGetText(out oldText))
+                    if (this.TryGetText(out var text) && oldDocument.TryGetText(out var oldText))
                     {
                         if (text == oldText)
                         {

src/Workspaces/Core/Portable/Workspace/Solution/DocumentState.cs

@@ -479,14 +479,12 @@ internal DocumentState UpdateTree(SyntaxNode newRoot, PreservationMode mode)
 
             // determine encoding
             Encoding encoding;
-            SyntaxTree priorTree;
-            SourceText priorText;
-            if (this.TryGetSyntaxTree(out priorTree))
+            if (this.TryGetSyntaxTree(out var priorTree))
             {
                 // this is most likely available since UpdateTree is normally called after modifying the existing tree.
                 encoding = priorTree.Encoding;
             }
-            else if (this.TryGetText(out priorText))
+            else if (this.TryGetText(out var priorText))
             {
                 encoding = priorText.Encoding;
             }
@@ -518,9 +516,7 @@ private VersionStamp GetNewTreeVersionForUpdatedTree(SyntaxNode newRoot, Version
                 return newTextVersion;
             }
 
-            TreeAndVersion oldTreeAndVersion;
-            SyntaxNode oldRoot;
-            if (!_treeSource.TryGetValue(out oldTreeAndVersion) || !oldTreeAndVersion.Tree.TryGetRoot(out oldRoot))
+            if (!_treeSource.TryGetValue(out var oldTreeAndVersion) || !oldTreeAndVersion.Tree.TryGetRoot(out var oldRoot))
             {
                 return newTextVersion;
             }
@@ -584,14 +580,12 @@ private static async Task<SourceText> BuildRecoverableTreeTextAsync(SyntaxTree t
 
         private VersionStamp GetNewerVersion()
         {
-            TextAndVersion textAndVersion;
-            if (this.textAndVersionSource.TryGetValue(out textAndVersion))
+            if (this.textAndVersionSource.TryGetValue(out var textAndVersion))
             {
                 return textAndVersion.Version.GetNewerVersion();
             }
 
-            TreeAndVersion treeAndVersion;
-            if (_treeSource.TryGetValue(out treeAndVersion) && treeAndVersion != null)
+            if (_treeSource.TryGetValue(out var treeAndVersion) && treeAndVersion != null)
             {
                 return treeAndVersion.Version.GetNewerVersion();
             }
@@ -602,9 +596,7 @@ private VersionStamp GetNewerVersion()
         public bool TryGetSyntaxTree(out SyntaxTree syntaxTree)
         {
             syntaxTree = default(SyntaxTree);
-
-            TreeAndVersion treeAndVersion;
-            if (_treeSource.TryGetValue(out treeAndVersion) && treeAndVersion != null)
+            if (_treeSource.TryGetValue(out var treeAndVersion) && treeAndVersion != null)
             {
                 syntaxTree = treeAndVersion.Tree;
                 BindSyntaxTreeToId(syntaxTree, this.Id);
@@ -634,8 +626,7 @@ internal SyntaxTree GetSyntaxTree(CancellationToken cancellationToken)
 
         public bool TryGetTopLevelChangeTextVersion(out VersionStamp version)
         {
-            TreeAndVersion treeAndVersion;
-            if (_treeSource.TryGetValue(out treeAndVersion) && treeAndVersion != null)
+            if (_treeSource.TryGetValue(out var treeAndVersion) && treeAndVersion != null)
             {
                 version = treeAndVersion.Version;
                 return true;
@@ -654,8 +645,7 @@ public override async Task<VersionStamp> GetTopLevelChangeTextVersionAsync(Cance
                 return await this.GetTextVersionAsync(cancellationToken).ConfigureAwait(false);
             }
 
-            TreeAndVersion treeAndVersion;
-            if (_treeSource.TryGetValue(out treeAndVersion) && treeAndVersion != null)
+            if (_treeSource.TryGetValue(out var treeAndVersion) && treeAndVersion != null)
             {
                 return treeAndVersion.Version;
             }
@@ -672,8 +662,7 @@ private static void BindSyntaxTreeToId(SyntaxTree tree, DocumentId id)
         {
             using (s_syntaxTreeToIdMapLock.DisposableWrite())
             {
-                DocumentId existingId;
-                if (s_syntaxTreeToIdMap.TryGetValue(tree, out existingId))
+                if (s_syntaxTreeToIdMap.TryGetValue(tree, out var existingId))
                 {
                     Contract.ThrowIfFalse(existingId == id);
                 }
@@ -688,8 +677,7 @@ public static DocumentId GetDocumentIdForTree(SyntaxTree tree)
         {
             using (s_syntaxTreeToIdMapLock.DisposableRead())
             {
-                DocumentId id;
-                s_syntaxTreeToIdMap.TryGetValue(tree, out id);
+                s_syntaxTreeToIdMap.TryGetValue(tree, out var id);
                 return id;
             }
         }

src/Workspaces/Core/Portable/Workspace/Solution/DocumentState_TreeTextSource.cs

@@ -39,8 +39,7 @@ public override TextAndVersion GetValue(CancellationToken cancellationToken = de
 
             public override bool TryGetValue(out TextAndVersion value)
             {
-                SourceText text;
-                if (_lazyText.TryGetValue(out text))
+                if (_lazyText.TryGetValue(out var text))
                 {
                     value = TextAndVersion.Create(text, _version, _filePath);
                     return true;

src/Workspaces/Core/Portable/Workspace/Solution/MetadataOnlyReference.cs

@@ -31,8 +31,7 @@ internal class MetadataOnlyReference
             CancellationToken cancellationToken)
         {
             solution.Workspace.LogTestMessage($"Looking to see if we already have a skeleton assembly for {projectReference.ProjectId} before we build one...");
-            MetadataReference reference;
-            if (TryGetReference(solution, projectReference, finalCompilation, version, out reference))
+            if (TryGetReference(solution, projectReference, finalCompilation, version, out var reference))
             {
                 solution.Workspace.LogTestMessage($"A reference was found {projectReference.ProjectId} so we're skipping the build.");
                 return reference;
@@ -93,8 +92,7 @@ internal class MetadataOnlyReference
             SolutionState solution, ProjectReference projectReference, Compilation finalOrDeclarationCompilation, VersionStamp version, out MetadataReference reference)
         {
             // if we have one from snapshot cache, use it. it will make sure same compilation will get same metadata reference always.
-            MetadataOnlyReferenceSet referenceSet;
-            if (s_snapshotCache.TryGetValue(finalOrDeclarationCompilation, out referenceSet))
+            if (s_snapshotCache.TryGetValue(finalOrDeclarationCompilation, out var referenceSet))
             {
                 solution.Workspace.LogTestMessage($"Found already cached metadata in {nameof(s_snapshotCache)} for the exact compilation");
                 reference = referenceSet.GetMetadataReference(finalOrDeclarationCompilation, projectReference.Aliases, projectReference.EmbedInteropTypes);
@@ -129,10 +127,8 @@ internal class MetadataOnlyReference
         {
             // get map for the branch
             var mapFromBranch = s_cache.GetValue(branchId, s_createReferenceSetMap);
-
             // if we have one, return it
-            MetadataOnlyReferenceSet referenceSet;
-            if (mapFromBranch.TryGetValue(projectReference.ProjectId, out referenceSet) &&
+            if (mapFromBranch.TryGetValue(projectReference.ProjectId, out var referenceSet) &&
                (version == VersionStamp.Default || referenceSet.Version == version))
             {
                 // record it to snapshot based cache.
@@ -181,9 +177,7 @@ public MetadataReference GetMetadataReference(Compilation compilation, Immutable
 
                 using (_gate.DisposableWait())
                 {
-                    WeakReference<MetadataReference> weakMetadata;
-                    MetadataReference metadataReference;
-                    if (!_metadataReferences.TryGetValue(key, out weakMetadata) || !weakMetadata.TryGetTarget(out metadataReference))
+                    if (!_metadataReferences.TryGetValue(key, out var weakMetadata) || !weakMetadata.TryGetTarget(out var metadataReference))
                     {
                         // here we give out strong reference to compilation. so there is possibility that we end up making 2 compilations for same project alive.
                         // one for final compilation and one for declaration only compilation. but the final compilation will be eventually kicked out from compilation cache

src/Workspaces/Core/Portable/Workspace/Solution/MetadataReferenceManager.cs

@@ -37,8 +37,7 @@ internal static Compilation GetCompilationForMetadataReference(ProjectState proj
         internal static bool TryGetCompilationForMetadataReference(ProjectState projectState, out Compilation referenceCompilation)
         {
             referenceCompilation = null;
-            WeakReference<Compilation> weakReference;
-            return s_compilationReferenceMap.TryGetValue(projectState, out weakReference) && weakReference.TryGetTarget(out referenceCompilation);
+            return s_compilationReferenceMap.TryGetValue(projectState, out var weakReference) && weakReference.TryGetTarget(out referenceCompilation);
         }
     }
 }
\ No newline at end of file

src/Workspaces/Core/Portable/Workspace/Solution/ProjectDependencyGraph.cs

@@ -51,8 +51,7 @@ public IImmutableSet<ProjectId> GetProjectsThatThisProjectDirectlyDependsOn(Proj
                 throw new ArgumentNullException(nameof(projectId));
             }
 
-            ImmutableHashSet<ProjectId> projectIds;
-            if (_referencesMap.TryGetValue(projectId, out projectIds))
+            if (_referencesMap.TryGetValue(projectId, out var projectIds))
             {
                 return projectIds;
             }
@@ -93,8 +92,7 @@ private ImmutableHashSet<ProjectId> GetProjectsThatDirectlyDependOnThisProject_N
                 _lazyReverseReferencesMap = this.ComputeReverseReferencesMap();
             }
 
-            ImmutableHashSet<ProjectId> reverseReferences;
-            if (_lazyReverseReferencesMap.TryGetValue(projectId, out reverseReferences))
+            if (_lazyReverseReferencesMap.TryGetValue(projectId, out var reverseReferences))
             {
                 return reverseReferences;
             }
@@ -113,8 +111,7 @@ private ImmutableHashSet<ProjectId> GetProjectsThatDirectlyDependOnThisProject_N
                 var references = kvp.Value;
                 foreach (var referencedId in references)
                 {
-                    HashSet<ProjectId> reverseReferences;
-                    if (!reverseReferencesMap.TryGetValue(referencedId, out reverseReferences))
+                    if (!reverseReferencesMap.TryGetValue(referencedId, out var reverseReferences))
                     {
                         reverseReferences = new HashSet<ProjectId>();
                         reverseReferencesMap.Add(referencedId, reverseReferences);
@@ -141,8 +138,7 @@ public IImmutableSet<ProjectId> GetProjectsThatThisProjectTransitivelyDependsOn(
 
             // first try without lock for speed
             var currentMap = _transitiveReferencesMap;
-            ImmutableHashSet<ProjectId> transitiveReferences;
-            if (currentMap.TryGetValue(projectId, out transitiveReferences))
+            if (currentMap.TryGetValue(projectId, out var transitiveReferences))
             {
                 return transitiveReferences;
             }
@@ -157,8 +153,7 @@ public IImmutableSet<ProjectId> GetProjectsThatThisProjectTransitivelyDependsOn(
 
         private ImmutableHashSet<ProjectId> GetProjectsThatThisProjectTransitivelyDependsOn_NoLock(ProjectId projectId)
         {
-            ImmutableHashSet<ProjectId> transitiveReferences;
-            if (!_transitiveReferencesMap.TryGetValue(projectId, out transitiveReferences))
+            if (!_transitiveReferencesMap.TryGetValue(projectId, out var transitiveReferences))
             {
                 using (var pooledObject = SharedPools.Default<HashSet<ProjectId>>().GetPooledObject())
                 {
@@ -197,8 +192,7 @@ public IEnumerable<ProjectId> GetProjectsThatTransitivelyDependOnThisProject(Pro
 
             // first try without lock for speed
             var currentMap = _reverseTransitiveReferencesMap;
-            ImmutableHashSet<ProjectId> reverseTransitiveReferences;
-            if (currentMap.TryGetValue(projectId, out reverseTransitiveReferences))
+            if (currentMap.TryGetValue(projectId, out var reverseTransitiveReferences))
             {
                 return reverseTransitiveReferences;
             }
@@ -213,9 +207,7 @@ public IEnumerable<ProjectId> GetProjectsThatTransitivelyDependOnThisProject(Pro
 
         private ImmutableHashSet<ProjectId> GetProjectsThatTransitivelyDependOnThisProject_NoLock(ProjectId projectId)
         {
-            ImmutableHashSet<ProjectId> reverseTransitiveReferences;
-
-            if (!_reverseTransitiveReferencesMap.TryGetValue(projectId, out reverseTransitiveReferences))
+            if (!_reverseTransitiveReferencesMap.TryGetValue(projectId, out var reverseTransitiveReferences))
             {
                 using (var pooledObject = SharedPools.Default<HashSet<ProjectId>>().GetPooledObject())
                 {
@@ -289,8 +281,7 @@ private IEnumerable<ProjectId> GetTopologicallySortedProjects_NoLock(Cancellatio
                 if (seenProjects.Add(projectId))
                 {
                     // Recurse and add anything this project depends on before adding the project itself.
-                    ImmutableHashSet<ProjectId> projectReferenceIds;
-                    if (_referencesMap.TryGetValue(projectId, out projectReferenceIds))
+                    if (_referencesMap.TryGetValue(projectId, out var projectReferenceIds))
                     {
                         TopologicalSort(projectReferenceIds, seenProjects, resultList, cancellationToken);
                     }

src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs

@@ -149,8 +149,7 @@ private static async Task<VersionStamp> ComputeLatestDocumentVersionAsync(Immuta
             ImmutableDictionary<DocumentId, DocumentState> newDocumentStates,
             ImmutableDictionary<DocumentId, TextDocumentState> newAdditionalDocumentStates)
         {
-            VersionStamp oldVersion;
-            if (_lazyLatestDocumentTopLevelChangeVersion.TryGetValue(out oldVersion))
+            if (_lazyLatestDocumentTopLevelChangeVersion.TryGetValue(out var oldVersion))
             {
                 return new AsyncLazy<VersionStamp>(c => ComputeTopLevelChangeTextVersionAsync(oldVersion, newDocument, c), cacheResult: true);
             }
@@ -319,15 +318,13 @@ public bool ContainsAdditionalDocument(DocumentId documentId)
 
         public DocumentState GetDocumentState(DocumentId documentId)
         {
-            DocumentState state;
-            _documentStates.TryGetValue(documentId, out state);
+            _documentStates.TryGetValue(documentId, out var state);
             return state;
         }
 
         public TextDocumentState GetAdditionalDocumentState(DocumentId documentId)
         {
-            TextDocumentState state;
-            _additionalDocumentStates.TryGetValue(documentId, out state);
+            _additionalDocumentStates.TryGetValue(documentId, out var state);
             return state;
         }
 
@@ -606,12 +603,9 @@ public ProjectState UpdateDocument(DocumentState newDocument, bool textChanged,
             }
 
             var newDocumentStates = this.DocumentStates.SetItem(newDocument.Id, newDocument);
-
-            AsyncLazy<VersionStamp> dependentDocumentVersion;
-            AsyncLazy<VersionStamp> dependentSemanticVersion;
             GetLatestDependentVersions(
                 newDocumentStates, _additionalDocumentStates, oldDocument, newDocument, recalculateDependentVersions, textChanged,
-                out dependentDocumentVersion, out dependentSemanticVersion);
+                out var dependentDocumentVersion, out var dependentSemanticVersion);
 
             return this.With(
                 documentStates: newDocumentStates,
@@ -630,12 +624,9 @@ public ProjectState UpdateAdditionalDocument(TextDocumentState newDocument, bool
             }
 
             var newDocumentStates = this.AdditionalDocumentStates.SetItem(newDocument.Id, newDocument);
-
-            AsyncLazy<VersionStamp> dependentDocumentVersion;
-            AsyncLazy<VersionStamp> dependentSemanticVersion;
             GetLatestDependentVersions(
                 _documentStates, newDocumentStates, oldDocument, newDocument, recalculateDependentVersions, textChanged,
-                out dependentDocumentVersion, out dependentSemanticVersion);
+                out var dependentDocumentVersion, out var dependentSemanticVersion);
 
             return this.With(
                 additionalDocumentStates: newDocumentStates,
@@ -655,17 +646,14 @@ public ProjectState UpdateAdditionalDocument(TextDocumentState newDocument, bool
 
             if (recalculateDependentVersions)
             {
-                VersionStamp oldVersion;
-                if (oldDocument.TryGetTextVersion(out oldVersion))
+                if (oldDocument.TryGetTextVersion(out var oldVersion))
                 {
-                    VersionStamp documentVersion;
-                    if (!_lazyLatestDocumentVersion.TryGetValue(out documentVersion) || documentVersion == oldVersion)
+                    if (!_lazyLatestDocumentVersion.TryGetValue(out var documentVersion) || documentVersion == oldVersion)
                     {
                         recalculateDocumentVersion = true;
                     }
 
-                    VersionStamp semanticVersion;
-                    if (!_lazyLatestDocumentTopLevelChangeVersion.TryGetValue(out semanticVersion) || semanticVersion == oldVersion)
+                    if (!_lazyLatestDocumentTopLevelChangeVersion.TryGetValue(out var semanticVersion) || semanticVersion == oldVersion)
                     {
                         recalculateSemanticVersion = true;
                     }

src/Workspaces/Core/Portable/Workspace/Solution/RecoverableTextAndVersion.cs

@@ -37,8 +37,7 @@ internal class RecoverableTextAndVersion : ValueSource<TextAndVersion>, ITextVer
 
         public override bool TryGetValue(out TextAndVersion value)
         {
-            SourceText text;
-            if (_text != null && _text.TryGetValue(out text))
+            if (_text != null && _text.TryGetValue(out var text))
             {
                 value = TextAndVersion.Create(text, _version, _filePath);
                 return true;
@@ -58,8 +57,7 @@ public bool TryGetTextVersion(out VersionStamp version)
             // then try to get version from cached value.
             if (version == default(VersionStamp))
             {
-                TextAndVersion textAndVersion;
-                if (this.TryGetValue(out textAndVersion))
+                if (this.TryGetValue(out var textAndVersion))
                 {
                     version = textAndVersion.Version;
                 }

src/Workspaces/Core/Portable/Workspace/Solution/Solution.cs

@@ -207,8 +207,7 @@ internal Document GetDocument(SyntaxTree syntaxTree, ProjectId projectId)
                     if (document != null)
                     {
                         // does this document really have the syntax tree?
-                        SyntaxTree documentTree;
-                        if (document.TryGetSyntaxTree(out documentTree) && documentTree == syntaxTree)
+                        if (document.TryGetSyntaxTree(out var documentTree) && documentTree == syntaxTree)
                         {
                             return document;
                         }

src/Workspaces/Core/Portable/Workspace/Solution/SolutionState.CompilationTracker.cs

@@ -156,10 +156,7 @@ public CompilationTracker Clone()
 
             public CompilationTracker FreezePartialStateWithTree(SolutionState solution, DocumentState docState, SyntaxTree tree, CancellationToken cancellationToken)
             {
-                ProjectState inProgressProject;
-                Compilation inProgressCompilation;
-
-                GetPartialCompilationState(solution, docState.Id, out inProgressProject, out inProgressCompilation, cancellationToken);
+                GetPartialCompilationState(solution, docState.Id, out var inProgressProject, out var inProgressCompilation, cancellationToken);
 
                 if (!inProgressCompilation.SyntaxTrees.Contains(tree))
                 {
@@ -300,8 +297,7 @@ public bool TryGetCompilation(out Compilation compilation)
 
             public Task<Compilation> GetCompilationAsync(SolutionState solution, CancellationToken cancellationToken)
             {
-                Compilation compilation;
-                if (this.TryGetCompilation(out compilation))
+                if (this.TryGetCompilation(out var compilation))
                 {
                     // PERF: This is a hot code path and Task<TResult> isn't cheap,
                     // so cache the completed tasks to reduce allocations. We also
@@ -726,11 +722,10 @@ private bool HasMissingReferences(Compilation compilation, IReadOnlyList<Metadat
             {
                 try
                 {
-                    Compilation compilation;
 
                     // if we already have the compilation and its right kind then use it.
                     if (this.ProjectState.LanguageServices == fromProject.LanguageServices
-                        && this.TryGetCompilation(out compilation))
+                        && this.TryGetCompilation(out var compilation))
                     {
                         return compilation.ToMetadataReference(projectReference.Aliases, projectReference.EmbedInteropTypes);
                     }
@@ -762,10 +757,8 @@ private bool HasMissingReferences(Compilation compilation, IReadOnlyList<Metadat
             public MetadataReference GetPartialMetadataReference(SolutionState solution, ProjectState fromProject, ProjectReference projectReference, CancellationToken cancellationToken)
             {
                 var state = this.ReadState();
-
                 // get compilation in any state it happens to be in right now.
-                Compilation compilation;
-                if (state.Compilation.TryGetValue(out compilation)
+                if (state.Compilation.TryGetValue(out var compilation)
                     && compilation != null
                     && this.ProjectState.LanguageServices == fromProject.LanguageServices)
                 {
@@ -790,12 +783,9 @@ public MetadataReference GetPartialMetadataReference(SolutionState solution, Pro
 
                         // get or build compilation up to declaration state. this compilation will be used to provide live xml doc comment
                         var declarationCompilation = await this.GetOrBuildDeclarationCompilationAsync(solution, cancellationToken: cancellationToken).ConfigureAwait(false);
-
-                        MetadataReference reference;
-
                         solution.Workspace.LogTestMessage($"Looking for a cached skeleton assembly for {projectReference.ProjectId} before taking the lock...");
 
-                        if (!MetadataOnlyReference.TryGetReference(solution, projectReference, declarationCompilation, version, out reference))
+                        if (!MetadataOnlyReference.TryGetReference(solution, projectReference, declarationCompilation, version, out var reference))
                         {
                             // using async build lock so we don't get multiple consumers attempting to build metadata-only images for the same compilation.
                             using (await _buildLock.DisposableWaitAsync(cancellationToken).ConfigureAwait(false))

src/Workspaces/Core/Portable/Workspace/Solution/SolutionState.cs

@@ -315,8 +315,7 @@ private DocumentState GetDocumentState(SyntaxTree syntaxTree, ProjectId projectI
                     if (document != null)
                     {
                         // does this document really have the syntax tree?
-                        SyntaxTree documentTree;
-                        if (document.TryGetSyntaxTree(out documentTree) && documentTree == syntaxTree)
+                        if (document.TryGetSyntaxTree(out var documentTree) && documentTree == syntaxTree)
                         {
                             return document;
                         }
@@ -353,8 +352,7 @@ public Task<VersionStamp> GetDependentSemanticVersionAsync(ProjectId projectId,
 
         public ProjectState GetProjectState(ProjectId projectId)
         {
-            ProjectState state;
-            _projectIdToProjectStateMap.TryGetValue(projectId, out state);
+            _projectIdToProjectStateMap.TryGetValue(projectId, out var state);
             return state;
         }
 
@@ -371,8 +369,7 @@ public ProjectState GetProjectState(IAssemblySymbol assemblySymbol, Cancellation
             // TODO: Remove this loop when we add source assembly symbols to s_assemblyOrModuleSymbolToProjectMap
             foreach (var state in _projectIdToProjectStateMap.Values)
             {
-                Compilation compilation;
-                if (this.TryGetCompilation(state.Id, out compilation))
+                if (this.TryGetCompilation(state.Id, out var compilation))
                 {
                     // if the symbol is the compilation's assembly symbol, we are done
                     if (compilation.Assembly == assemblySymbol)
@@ -382,8 +379,7 @@ public ProjectState GetProjectState(IAssemblySymbol assemblySymbol, Cancellation
                 }
             }
 
-            ProjectId id;
-            s_assemblyOrModuleSymbolToProjectMap.TryGetValue(assemblySymbol, out id);
+            s_assemblyOrModuleSymbolToProjectMap.TryGetValue(assemblySymbol, out var id);
             return id == null ? null : this.GetProjectState(id);
         }
 
@@ -400,8 +396,7 @@ private static CompilationTracker CreateCompilationTracker(ProjectId projectId,
 
         private CompilationTracker GetCompilationTracker(ProjectId projectId)
         {
-            CompilationTracker tracker;
-            if (!_projectIdToTrackerMap.TryGetValue(projectId, out tracker))
+            if (!_projectIdToTrackerMap.TryGetValue(projectId, out var tracker))
             {
                 tracker = ImmutableInterlocked.GetOrAdd(ref _projectIdToTrackerMap, projectId, s_createCompilationTrackerFunction, this);
             }
@@ -486,8 +481,7 @@ public SolutionState AddProject(ProjectInfo projectInfo)
                     continue;
                 }
 
-                ImmutableArray<DocumentId> documentIdsWithPath;
-                builder[filePath] = builder.TryGetValue(filePath, out documentIdsWithPath)
+                builder[filePath] = builder.TryGetValue(filePath, out var documentIdsWithPath)
                     ? documentIdsWithPath.Add(documentId)
                     : ImmutableArray.Create(documentId);
             }
@@ -546,8 +540,7 @@ public SolutionState RemoveProject(ProjectId projectId)
                     continue;
                 }
 
-                ImmutableArray<DocumentId> documentIdsWithPath;
-                if (!builder.TryGetValue(filePath, out documentIdsWithPath) || !documentIdsWithPath.Contains(documentId))
+                if (!builder.TryGetValue(filePath, out var documentIdsWithPath) || !documentIdsWithPath.Contains(documentId))
                 {
                     throw new ArgumentException("The given documentId was not found in the linkedFilesMap.");
                 }
@@ -1137,9 +1130,7 @@ public SolutionState WithDocumentText(DocumentId documentId, SourceText text, Pr
             CheckContainsDocument(documentId);
 
             var oldDocument = this.GetDocumentState(documentId);
-
-            SourceText oldText;
-            if (oldDocument.TryGetText(out oldText) && text == oldText)
+            if (oldDocument.TryGetText(out var oldText) && text == oldText)
             {
                 return this;
             }
@@ -1184,9 +1175,7 @@ public SolutionState WithAdditionalDocumentText(DocumentId documentId, SourceTex
             CheckContainsAdditionalDocument(documentId);
 
             var oldDocument = this.GetAdditionalDocumentState(documentId);
-
-            SourceText oldText;
-            if (oldDocument.TryGetText(out oldText) && text == oldText)
+            if (oldDocument.TryGetText(out var oldText) && text == oldText)
             {
                 return this;
             }
@@ -1276,11 +1265,8 @@ public SolutionState WithDocumentSyntaxRoot(DocumentId documentId, SyntaxNode ro
             CheckContainsDocument(documentId);
 
             var oldDocument = this.GetDocumentState(documentId);
-
-            SyntaxTree oldTree;
-            SyntaxNode oldRoot;
-            if (oldDocument.TryGetSyntaxTree(out oldTree) &&
-                oldTree.TryGetRoot(out oldRoot) &&
+            if (oldDocument.TryGetSyntaxTree(out var oldTree) &&
+                oldTree.TryGetRoot(out var oldRoot) &&
                 oldRoot == root)
             {
                 return this;
@@ -1432,11 +1418,9 @@ private SolutionState WithTextDocumentState(TextDocumentState newDocument, bool
             var newStateMap = _projectIdToProjectStateMap.SetItem(projectId, newProjectState);
             var newDependencyGraph = withProjectReferenceChange ? CreateDependencyGraph(_projectIds, newStateMap) : _dependencyGraph;
             var newTrackerMap = CreateCompilationTrackerMap(projectId, newDependencyGraph);
-
             // If we have a tracker for this project, then fork it as well (along with the
             // translation action and store it in the tracker map.
-            CompilationTracker tracker;
-            if (newTrackerMap.TryGetValue(projectId, out tracker))
+            if (newTrackerMap.TryGetValue(projectId, out var tracker))
             {
                 newTrackerMap = newTrackerMap.Remove(projectId);
 
@@ -1468,8 +1452,7 @@ public ImmutableArray<DocumentId> GetDocumentIdsWithFilePath(string filePath)
                 return ImmutableArray.Create<DocumentId>();
             }
 
-            ImmutableArray<DocumentId> documentIds;
-            return _linkedFilesMap.TryGetValue(filePath, out documentIds)
+            return _linkedFilesMap.TryGetValue(filePath, out var documentIds)
                 ? documentIds
                 : ImmutableArray.Create<DocumentId>();
         }
@@ -1620,8 +1603,7 @@ public SolutionState WithDocumentText(IEnumerable<DocumentId> documentIds, Sourc
                 var doc = solution.GetDocumentState(documentId);
                 if (doc != null)
                 {
-                    SourceText existingText;
-                    if (!doc.TryGetText(out existingText) || existingText != text)
+                    if (!doc.TryGetText(out var existingText) || existingText != text)
                     {
                         solution = solution.WithDocumentText(documentId, text, mode);
                     }
@@ -1634,11 +1616,9 @@ public SolutionState WithDocumentText(IEnumerable<DocumentId> documentIds, Sourc
         public bool TryGetCompilation(ProjectId projectId, out Compilation compilation)
         {
             CheckContainsProject(projectId);
-
-            CompilationTracker tracker;
             compilation = null;
 
-            return this.TryGetCompilationTracker(projectId, out tracker)
+            return this.TryGetCompilationTracker(projectId, out var tracker)
                 && tracker.TryGetCompilation(out compilation);
         }
 
@@ -1688,10 +1668,8 @@ private static void RecordSourceOfAssemblySymbol(ISymbol assemblyOrModuleSymbol,
             }
 
             Contract.ThrowIfNull(projectId);
-
             // remember which project is associated with this assembly
-            ProjectId tmp;
-            if (!s_assemblyOrModuleSymbolToProjectMap.TryGetValue(assemblyOrModuleSymbol, out tmp))
+            if (!s_assemblyOrModuleSymbolToProjectMap.TryGetValue(assemblyOrModuleSymbol, out var tmp))
             {
                 // use GetValue to avoid race condition exceptions from Add.
                 // the first one to set the value wins.
@@ -1734,8 +1712,7 @@ public Task<MetadataReference> GetMetadataReferenceAsync(ProjectReference projec
         {
             // Try to get the compilation state for this project.  If it doesn't exist, don't do any
             // more work.  
-            CompilationTracker state;
-            if (!_projectIdToTrackerMap.TryGetValue(projectReference.ProjectId, out state))
+            if (!_projectIdToTrackerMap.TryGetValue(projectReference.ProjectId, out var state))
             {
                 return null;
             }

src/Workspaces/Core/Portable/Workspace/Solution/StateChecksums.cs

@@ -34,10 +34,8 @@ public SolutionStateChecksums With(Checksum infoChecksum = null, ProjectChecksum
             CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
             // verify input
-            SolutionStateChecksums stateChecksum;
-            Contract.ThrowIfFalse(state.TryGetStateChecksums(out stateChecksum));
+            Contract.ThrowIfFalse(state.TryGetStateChecksums(out var stateChecksum));
             Contract.ThrowIfFalse(this == stateChecksum);
 
             if (searchingChecksumsLeft.Remove(Checksum))
@@ -58,10 +56,8 @@ public SolutionStateChecksums With(Checksum infoChecksum = null, ProjectChecksum
             foreach (var kv in state.ProjectStates)
             {
                 var projectState = kv.Value;
-
                 // solution state checksum can't be created without project state checksums created first
-                ProjectStateChecksums projectStateChecksums;
-                Contract.ThrowIfFalse(projectState.TryGetStateChecksums(out projectStateChecksums));
+                Contract.ThrowIfFalse(projectState.TryGetStateChecksums(out var projectStateChecksums));
 
                 projectStateChecksums.Find(projectState, searchingChecksumsLeft, result, cancellationToken);
                 if (searchingChecksumsLeft.Count == 0)
@@ -139,10 +135,8 @@ public ProjectStateChecksums(params object[] children) : base(nameof(ProjectStat
             CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
             // verify input
-            ProjectStateChecksums stateChecksum;
-            Contract.ThrowIfFalse(state.TryGetStateChecksums(out stateChecksum));
+            Contract.ThrowIfFalse(state.TryGetStateChecksums(out var stateChecksum));
             Contract.ThrowIfFalse(this == stateChecksum);
 
             if (searchingChecksumsLeft.Remove(Checksum))
@@ -206,9 +200,7 @@ public ProjectStateChecksums(params object[] children) : base(nameof(ProjectStat
             foreach (var kv in values)
             {
                 var state = kv.Value;
-
-                DocumentStateChecksums stateChecksums;
-                Contract.ThrowIfFalse(state.TryGetStateChecksums(out stateChecksums));
+                Contract.ThrowIfFalse(state.TryGetStateChecksums(out var stateChecksums));
 
                 stateChecksums.Find(state, searchingChecksumsLeft, result, cancellationToken);
                 if (searchingChecksumsLeft.Count == 0)
@@ -273,10 +265,8 @@ public DocumentStateChecksums With(Checksum infoChecksum = null, Checksum textCh
             CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
             // verify input
-            DocumentStateChecksums stateChecksum;
-            Contract.ThrowIfFalse(state.TryGetStateChecksums(out stateChecksum));
+            Contract.ThrowIfFalse(state.TryGetStateChecksums(out var stateChecksum));
             Contract.ThrowIfFalse(this == stateChecksum);
 
             if (searchingChecksumsLeft.Remove(Checksum))

src/Workspaces/Core/Portable/Workspace/Solution/TextDocumentState.cs

@@ -191,8 +191,7 @@ public bool TryGetText(out SourceText text)
                 return true;
             }
 
-            TextAndVersion textAndVersion;
-            if (this.textAndVersionSource.TryGetValue(out textAndVersion))
+            if (this.textAndVersionSource.TryGetValue(out var textAndVersion))
             {
                 text = textAndVersion.Text;
                 return true;
@@ -213,8 +212,7 @@ public bool TryGetTextVersion(out VersionStamp version)
                 return versionable.TryGetTextVersion(out version);
             }
 
-            TextAndVersion textAndVersion;
-            if (this.textAndVersionSource.TryGetValue(out textAndVersion))
+            if (this.textAndVersionSource.TryGetValue(out var textAndVersion))
             {
                 version = textAndVersion.Version;
                 return true;
@@ -246,14 +244,12 @@ public SourceText GetText(CancellationToken cancellationToken)
         public async Task<VersionStamp> GetTextVersionAsync(CancellationToken cancellationToken)
         {
             // try fast path first
-            VersionStamp version;
-            if (TryGetTextVersion(out version))
+            if (TryGetTextVersion(out var version))
             {
                 return version;
             }
 
-            TextAndVersion textAndVersion;
-            if (this.textAndVersionSource.TryGetValue(out textAndVersion))
+            if (this.textAndVersionSource.TryGetValue(out var textAndVersion))
             {
                 return textAndVersion.Version;
             }
@@ -319,8 +315,7 @@ public TextDocumentState UpdateText(TextLoader loader, PreservationMode mode)
 
         private VersionStamp GetNewerVersion()
         {
-            TextAndVersion textAndVersion;
-            if (this.textAndVersionSource.TryGetValue(out textAndVersion))
+            if (this.textAndVersionSource.TryGetValue(out var textAndVersion))
             {
                 return textAndVersion.Version.GetNewerVersion();
             }

src/Workspaces/Core/Portable/Workspace/TextExtensions.cs

@@ -15,8 +15,7 @@ internal static class TextExtensions
         /// </summary>
         public static IEnumerable<Document> GetRelatedDocumentsWithChanges(this SourceText text)
         {
-            Workspace workspace;
-            if (Workspace.TryGetWorkspace(text.Container, out workspace))
+            if (Workspace.TryGetWorkspace(text.Container, out var workspace))
             {
                 var ids = workspace.GetRelatedDocumentIds(text.Container);
                 var sol = workspace.CurrentSolution.WithDocumentText(ids, text, PreservationMode.PreserveIdentity);
@@ -32,8 +31,7 @@ public static IEnumerable<Document> GetRelatedDocumentsWithChanges(this SourceTe
         /// </summary>
         public static Document GetOpenDocumentInCurrentContextWithChanges(this SourceText text)
         {
-            Workspace workspace;
-            if (Workspace.TryGetWorkspace(text.Container, out workspace))
+            if (Workspace.TryGetWorkspace(text.Container, out var workspace))
             {
                 var id = workspace.GetDocumentIdInCurrentContext(text.Container);
                 if (id == null || !workspace.CurrentSolution.ContainsDocument(id))
@@ -53,8 +51,7 @@ public static Document GetOpenDocumentInCurrentContextWithChanges(this SourceTex
         /// </summary>
         public static IEnumerable<Document> GetRelatedDocuments(this SourceTextContainer container)
         {
-            Workspace workspace;
-            if (Workspace.TryGetWorkspace(container, out workspace))
+            if (Workspace.TryGetWorkspace(container, out var workspace))
             {
                 var sol = workspace.CurrentSolution;
                 var ids = workspace.GetRelatedDocumentIds(container);
@@ -70,8 +67,7 @@ public static IEnumerable<Document> GetRelatedDocuments(this SourceTextContainer
         /// </summary>
         public static Document GetOpenDocumentInCurrentContext(this SourceTextContainer container)
         {
-            Workspace workspace;
-            if (Workspace.TryGetWorkspace(container, out workspace))
+            if (Workspace.TryGetWorkspace(container, out var workspace))
             {
                 var id = workspace.GetDocumentIdInCurrentContext(container);
                 return workspace.CurrentSolution.GetDocument(id);

src/Workspaces/Core/Portable/Workspace/Workspace.cs

@@ -903,11 +903,10 @@ private static Solution UpdateReferencesAfterAdd(Solution solution)
                     var pemeta = meta as PortableExecutableReference;
                     if (pemeta != null)
                     {
-                        ProjectId matchingProjectId;
 
                         // check both Display and FilePath. FilePath points to the actually bits, but Display should match output path if 
                         // the metadata reference is shadow copied.
-                        if ((!string.IsNullOrEmpty(pemeta.Display) && outputAssemblyToProjectIdMap.TryGetValue(pemeta.Display, out matchingProjectId)) ||
+                        if ((!string.IsNullOrEmpty(pemeta.Display) && outputAssemblyToProjectIdMap.TryGetValue(pemeta.Display, out var matchingProjectId)) ||
                             (!string.IsNullOrEmpty(pemeta.FilePath) && outputAssemblyToProjectIdMap.TryGetValue(pemeta.FilePath, out matchingProjectId)))
                         {
                             var newProjRef = new ProjectReference(matchingProjectId, pemeta.Properties.Aliases, pemeta.Properties.EmbedInteropTypes);
@@ -1226,20 +1225,16 @@ protected virtual void ApplyProjectChanges(ProjectChanges projectChanges)
         {
             var oldDoc = projectChanges.OldProject.GetDocument(documentId);
             var newDoc = projectChanges.NewProject.GetDocument(documentId);
-
             // see whether we can get oldText
-            SourceText oldText;
-            if (!oldDoc.TryGetText(out oldText))
+            if (!oldDoc.TryGetText(out var oldText))
             {
                 // we can't get old text, there is not much we can do except replacing whole text.
                 var currentText = newDoc.GetTextAsync(CancellationToken.None).WaitAndGetResult_CanCallOnBackground(CancellationToken.None); // needs wait
                 this.ApplyDocumentTextChanged(documentId, currentText);
                 return;
             }
-
             // see whether we can get new text
-            SourceText newText;
-            if (!newDoc.TryGetText(out newText))
+            if (!newDoc.TryGetText(out var newText))
             {
                 // okay, we have old text, but no new text. let document determine text changes
                 var textChanges = newDoc.GetTextChangesAsync(oldDoc, CancellationToken.None).WaitAndGetResult_CanCallOnBackground(CancellationToken.None); // needs wait

src/Workspaces/Core/Portable/Workspace/Workspace_Editor.cs

@@ -39,8 +39,7 @@ internal virtual bool CanChangeActiveContextDocument
 
         private static void RemoveIfEmpty<TKey, TValue>(IDictionary<TKey, ISet<TValue>> dictionary, TKey key)
         {
-            ISet<TValue> values;
-            if (dictionary.TryGetValue(key, out values))
+            if (dictionary.TryGetValue(key, out var values))
             {
                 if (values.Count == 0)
                 {
@@ -103,19 +102,14 @@ protected void ClearOpenDocument(DocumentId documentId, bool isSolutionClosing =
         private DocumentId ClearOpenDocument_NoLock(DocumentId documentId)
         {
             _stateLock.AssertHasLock();
-
-            ISet<DocumentId> openDocIds;
-
-            if (_projectToOpenDocumentsMap.TryGetValue(documentId.ProjectId, out openDocIds) && openDocIds != null)
+            if (_projectToOpenDocumentsMap.TryGetValue(documentId.ProjectId, out var openDocIds) && openDocIds != null)
             {
                 openDocIds.Remove(documentId);
             }
 
             RemoveIfEmpty(_projectToOpenDocumentsMap, documentId.ProjectId);
-
             // Stop tracking the buffer or update the documentId associated with the buffer.
-            TextTracker tracker;
-            if (_textTrackers.TryGetValue(documentId, out tracker))
+            if (_textTrackers.TryGetValue(documentId, out var tracker))
             {
                 tracker.Disconnect();
                 _textTrackers.Remove(documentId);
@@ -217,8 +211,7 @@ public virtual IEnumerable<DocumentId> GetOpenDocumentIds(ProjectId projectId =
 
                 if (projectId != null)
                 {
-                    ISet<DocumentId> documentIds;
-                    if (_projectToOpenDocumentsMap.TryGetValue(projectId, out documentIds))
+                    if (_projectToOpenDocumentsMap.TryGetValue(projectId, out var documentIds))
                     {
                         return documentIds;
                     }
@@ -249,8 +242,7 @@ public virtual IEnumerable<DocumentId> GetRelatedDocumentIds(SourceTextContainer
 
         private ImmutableArray<DocumentId> GetRelatedDocumentIds_NoLock(SourceTextContainer container)
         {
-            DocumentId documentId;
-            if (!_bufferToDocumentInCurrentContextMap.TryGetValue(container, out documentId))
+            if (!_bufferToDocumentInCurrentContextMap.TryGetValue(container, out var documentId))
             {
                 // it is not an opened file
                 return ImmutableArray<DocumentId>.Empty;
@@ -308,8 +300,7 @@ private SourceTextContainer GetOpenDocumentSourceTextContainer_NoLock(DocumentId
 
         private DocumentId GetDocumentIdInCurrentContext_NoLock(SourceTextContainer container)
         {
-            DocumentId docId;
-            bool foundValue = _bufferToDocumentInCurrentContextMap.TryGetValue(container, out docId);
+            bool foundValue = _bufferToDocumentInCurrentContextMap.TryGetValue(container, out var docId);
 
             if (foundValue)
             {
@@ -391,10 +382,7 @@ protected void CheckDocumentIsOpen(DocumentId documentId)
         private ISet<DocumentId> GetProjectOpenDocuments_NoLock(ProjectId project)
         {
             _stateLock.AssertHasLock();
-
-            ISet<DocumentId> openDocs;
-
-            _projectToOpenDocumentsMap.TryGetValue(project, out openDocs);
+            _projectToOpenDocumentsMap.TryGetValue(project, out var openDocs);
             return openDocs;
         }
 
@@ -415,11 +403,8 @@ private ISet<DocumentId> GetProjectOpenDocuments_NoLock(ProjectId project)
 
                 var newText = textContainer.CurrentText;
                 Solution currentSolution;
-
-                SourceText oldText;
-                VersionStamp version;
-                if (oldDocument.TryGetText(out oldText) &&
-                    oldDocument.TryGetTextVersion(out version))
+                if (oldDocument.TryGetText(out var oldText) &&
+                    oldDocument.TryGetTextVersion(out var version))
                 {
                     // Optimize the case where we've already got the previous text and version.
                     var newTextAndVersion = GetProperTextAndVersion(oldText, newText, version, oldDocumentState.FilePath);
@@ -657,11 +642,9 @@ private DocumentId UpdateCurrentContextMapping_NoLock(SourceTextContainer textCo
         private SourceText GetOpenDocumentText(Solution solution, DocumentId documentId)
         {
             CheckDocumentIsOpen(documentId);
-
-            // text should always be preserved, so TryGetText will succeed.
-            SourceText text;
             var doc = solution.GetDocument(documentId);
-            doc.TryGetText(out text);
+            // text should always be preserved, so TryGetText will succeed.
+            doc.TryGetText(out var text);
             return text;
         }