Turn implicit conversion into compiled templates

src/StructId.Analyzer/ConstructorGenerator.cs

@@ -11,6 +11,8 @@ public class ConstructorGenerator() : BaseGenerator(
     ThisAssembly.Resources.Templates.ConstructorT.Text,
     ReferenceCheck.TypeExists)
 {
+    // NOTE: since we only emit the ctor if the struct doesn't already have one, 
+    // we cannot switch this to the simpler compiled templates, which don't have conditional logic
     protected override IncrementalValuesProvider<TemplateArgs> OnInitialize(IncrementalGeneratorInitializationContext context, IncrementalValuesProvider<TemplateArgs> source)
         => base.OnInitialize(context, source.Where(x
             => x.StructId.DeclaringSyntaxReferences.Select(r => r.GetSyntax()).OfType<TypeDeclarationSyntax>().All(s => s.ParameterList == null)));

src/StructId.Analyzer/TemplatedGenerator.cs

@@ -187,7 +187,7 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
                 var type = idType.DeclaringSyntaxReferences[0].GetSyntax(cancellation) as TypeDeclarationSyntax;
                 var iface = type?.BaseList?.Types.FirstOrDefault()?.Type;
                 if (type == null || iface == null)
-                    return new Template(structId, idType, attribute, known);
+                    return new Template(structId, idType, attribute, known) { OriginalTId = idType };
 
                 if (x.Right.Compilation.GetSemanticModel(type.SyntaxTree).GetSymbolInfo(iface).Symbol is not INamedTypeSymbol ifaceType)
                     return new Template(structId, idType, attribute, known);

src/StructId/Templates/Conversion.cs

@@ -0,0 +1,10 @@
+// <auto-generated />
+
+using StructId;
+
+[TStructId]
+file partial record struct TSelf(string Value)
+{
+    public static implicit operator string(TSelf id) => id.Value;
+    public static explicit operator TSelf(string value) => new(value);
+}

src/StructId/ResourceTemplates/ConversionT.cs → src/StructId/Templates/ConversionT.cs

@@ -1,7 +1,12 @@
 // <auto-generated />
 
-readonly partial record struct TSelf
+using StructId;
+
+[TStructId]
+file partial record struct TSelf(TId Value)
 {
     public static implicit operator TId(TSelf id) => id.Value;
     public static explicit operator TSelf(TId value) => new(value);
-}
+}
+
+file record struct TId;