Remove Lookup usage to improve performance (#725)

Author: sebastienros

.editorconfig

@@ -89,6 +89,9 @@ csharp_style_prefer_range_operator = false
 dotnet_diagnostic.IDE1006.severity = silent
 csharp_prefer_system_threading_lock = true:suggestion
 
+# IDE0078: Use pattern matching
+dotnet_diagnostic.IDE0078.severity = silent
+
 [*.{cs,vb}]
 #### Naming styles ####
 

Directory.Packages.props

@@ -16,7 +16,7 @@
     <PackageVersion Include="System.Reflection.Emit.Lightweight" Version="4.7.0" />
 
     <!-- Common to all TFMs -->
-    <PackageVersion Include="Parlot" Version="1.2.1" />
+    <PackageVersion Include="Parlot" Version="1.2.2" />
     <PackageVersion Include="TimeZoneConverter" Version="6.1.0" />
 
     <!-- Benchmarks -->

Fluid.Benchmarks/FluidBenchmarks.cs

@@ -1,13 +1,14 @@
-using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Attributes;
 
 namespace Fluid.Benchmarks
 {
-    [MemoryDiagnoser, ShortRunJob]
+    [MemoryDiagnoser]
     public class FluidBenchmarks : BaseBenchmarks
     {
         private readonly TemplateOptions _options = new TemplateOptions();
         private readonly FluidParser _parser  = new FluidParser();
         private readonly IFluidTemplate _fluidTemplate;
+        private readonly FluidParser _compiledParser = new FluidParser().Compile();
 
         public FluidBenchmarks()
         {
@@ -28,6 +29,18 @@ public override object ParseBig()
             return _parser.Parse(BlogPostTemplate);
         }
 
+        [Benchmark]
+        public object ParseCompiled()
+        {
+            return _compiledParser.Parse(ProductTemplate);
+        }
+
+        [Benchmark]
+        public object ParseBigCompiled()
+        {
+            return _compiledParser.Parse(BlogPostTemplate);
+        }
+
         [Benchmark]
         public override string Render()
         {

Fluid/FluidParser.cs

@@ -4,7 +4,6 @@
 using Fluid.Values;
 using Parlot;
 using Parlot.Fluent;
-using Parlot.Rewriting;
 using System.Globalization;
 using System.Runtime.CompilerServices;
 using System.Text.Encodings.Web;
@@ -52,8 +51,7 @@ public class FluidParser
         protected readonly Parser<IReadOnlyList<FunctionCallArgument>> FunctionCallArgumentsList;
         protected readonly Parser<Expression> LogicalExpression;
         protected readonly Parser<Expression> CombinatoryExpression; // and | or
-        protected readonly Parser<Expression> Primary;
-        protected readonly Deferred<Expression> PrimaryInternal = Deferred<Expression>();
+        protected readonly Deferred<Expression> Primary = Deferred<Expression>();
         protected readonly Deferred<Expression> FilterExpression = Deferred<Expression>();
         protected readonly Deferred<IReadOnlyList<Statement>> KnownTagsList = Deferred<IReadOnlyList<Statement>>();
         protected readonly Deferred<IReadOnlyList<Statement>> AnyTagsList = Deferred<IReadOnlyList<Statement>>();
@@ -78,9 +76,6 @@ public FluidParser(FluidParserOptions parserOptions)
             String.Name = "String";
             Number.Name = "Number";
 
-            // Build lookup for String/Member/Number/Range
-            Primary = PrimaryInternal.Lookup((ISeekable)String, (ISeekable)new IdentifierParser(), (ISeekable)Number, (ISeekable)LParen);
-
             var Integer = Terms.Integer().Then<Expression>(x => new LiteralExpression(NumberValue.Create(x)));
             Integer.Name = "Integer";
 
@@ -128,7 +123,7 @@ public FluidParser(FluidParserOptions parserOptions)
             Range.Name = "Range";
 
             // primary => NUMBER | STRING | property
-            PrimaryInternal.Parser =
+            Primary.Parser =
                 String.Then<Expression>(x => new LiteralExpression(StringValue.Create(x)))
                 .Or(Member.Then<Expression>(static x =>
                 {