Minor code refactoring for re-use.

src/Generator/Generators/C/CppTypePrinter.cs

@@ -584,7 +584,8 @@ namespace CppSharp.Generators.C
                         args.Add(arg.Type.Visit(this));
                         break;
                     case TemplateArgument.ArgumentKind.Declaration:
-                        args.Add(arg.Declaration.Visit(this));
+                        if (arg.Declaration != null)
+                            args.Add(arg.Declaration.Visit(this));
                         break;
                     case TemplateArgument.ArgumentKind.Integral:
                         ClassTemplate template = specialization.TemplatedDecl;
@@ -596,6 +597,7 @@ namespace CppSharp.Generators.C
                         {
                             args.Add(arg.Integral.ToString(CultureInfo.InvariantCulture));
                         }
+
                         break;
                 }
             }
@@ -634,7 +636,7 @@ namespace CppSharp.Generators.C
             CppSharp.AST.Type desugared = function.FunctionType.Type.Desugar();
             if (!desugared.IsPointerTo(out functionType))
                 functionType = (FunctionType)desugared;
-            string exceptionType = Print(functionType.ExceptionSpecType);
+            string exceptionType = functionType != null ? Print(functionType.ExceptionSpecType) : "";
 
             var @return = function.OriginalReturnType.Visit(this);
             @return.Name = @class + name;

src/Generator/Generators/CodeGenerator.cs

@@ -316,7 +316,7 @@ namespace CppSharp.Generators
                 property.Visit(this);
             }
 
-            VisitClassConstructors(@class);
+            VisitClassConstructors(@class.Constructors.Where(c => !ASTUtils.CheckIgnoreMethod(c)));
             VisitClassMethods(@class);
 
             return true;
@@ -333,9 +333,9 @@ namespace CppSharp.Generators
             }
         }
 
-        public virtual void VisitClassConstructors(Class @class)
+        public virtual void VisitClassConstructors(IEnumerable<Method> constructors)
         {
-            foreach (var ctor in @class.Constructors.Where(c => !ASTUtils.CheckIgnoreMethod(c)))
+            foreach (var ctor in constructors)
             {
                 ctor.Visit(this);
             }

src/Generator/Generators/NAPI/NAPIHelpers.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.IO;
 using System.Linq;
 using CppSharp.AST;
 using CppSharp.AST.Extensions;
@@ -9,11 +10,9 @@ using CppSharp.Generators.NAPI;
 
 namespace CppSharp.Generators.Cpp
 {
-    public class NAPICodeGenerator : CCodeGenerator
+    public class MethodGroupCodeGenerator : CCodeGenerator
     {
-        public override string FileExtension => "cpp";
+        protected MethodGroupCodeGenerator(BindingContext context, IEnumerable<TranslationUnit> units)
-
-        public NAPICodeGenerator(BindingContext context, IEnumerable<TranslationUnit> units)
             : base(context, units)
         {
         }
@@ -43,9 +42,9 @@ namespace CppSharp.Generators.Cpp
             return VisitClassDeclContext(@class);
         }
 
-        public override void VisitClassConstructors(Class @class)
+        public override void VisitClassConstructors(IEnumerable<Method> ctors)
         {
-            var constructors = @class.Constructors.Where(c => c.IsGenerated && !c.IsCopyConstructor)
+            var constructors = ctors.Where(c => c.IsGenerated && !c.IsCopyConstructor)
                 .ToList();
 
             if (!constructors.Any())
@@ -59,7 +58,7 @@ namespace CppSharp.Generators.Cpp
             if (!function.IsGenerated)
                 return false;
 
-            if (!(function is Method method))
+            if (function is not Method method)
                 return true;
 
             if (method.IsConstructor || method.IsDestructor)
@@ -88,10 +87,27 @@ namespace CppSharp.Generators.Cpp
             foreach (var method in @group)
             {
                 method.Visit(this);
-                return;
             }
         }
 
+        public static string GetTranslationUnitName(TranslationUnit unit)
+        {
+            var paths = unit.FileRelativePath.Split('/').ToList();
+            paths = paths.Select(p => Path.GetFileNameWithoutExtension(p.ToLowerInvariant())).ToList();
+            var name = string.Join('_', paths);
+            return name;
+        }
+    }
+
+    public class NAPICodeGenerator : MethodGroupCodeGenerator
+    {
+        public override string FileExtension => "cpp";
+
+        public NAPICodeGenerator(BindingContext context, IEnumerable<TranslationUnit> units)
+            : base(context, units)
+        {
+        }
+
         public virtual MarshalPrinter<MarshalContext, CppTypePrinter> GetMarshalManagedToNativePrinter(MarshalContext ctx)
         {
             return new NAPIMarshalManagedToNativePrinter(ctx);

src/Generator/Generators/NAPI/NAPISources.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Globalization;
 using System.IO;
 using System.Linq;
 using CppSharp.AST;
@@ -24,14 +23,6 @@ namespace CppSharp.Generators.Cpp
         {
         }
 
-        public static string GetTranslationUnitName(TranslationUnit unit)
-        {
-            var paths = unit.FileRelativePath.Split('/').ToList();
-            paths = paths.Select(p => Path.GetFileNameWithoutExtension(p.ToLowerInvariant())).ToList();
-            var name = string.Join('_', paths);
-            return name;
-        }
-
         public override void Process()
         {
             GenerateFilePreamble(CommentKind.BCPL);

src/Generator/Generators/QuickJS/QuickJSSources.cs

@@ -198,7 +198,7 @@ namespace CppSharp.Generators.Cpp
         {
         }
 
-        public override void VisitClassConstructors(Class @class)
+        public override void VisitClassConstructors(IEnumerable<Method> ctors)
         {
         }