Introduce a new is_annotation helper for InstructionIndex

src/compiler/include/sourcemeta/blaze/compiler_output.h

@@ -169,7 +169,7 @@ class SOURCEMETA_BLAZE_COMPILER_EXPORT TraceOutput {
   TraceOutput(const ErrorOutput &) = delete;
   auto operator=(const TraceOutput &) -> TraceOutput & = delete;
 
-  enum class EntryType { Push, Pass, Fail };
+  enum class EntryType { Push, Pass, Fail, Annotation };
 
   struct Entry {
     const EntryType type;

src/evaluator/include/sourcemeta/blaze/evaluator_instruction.h

@@ -207,6 +207,21 @@ constexpr std::string_view InstructionNames[] = {
     "ControlJump",
     "ControlDynamicAnchorJump"};
 
+/// @ingroup evaluator
+/// Check if a given instruction type corresponds to an annotation
+inline auto is_annotation(const InstructionIndex type) noexcept -> bool {
+  switch (type) {
+    case InstructionIndex::AnnotationBasenameToParent:
+      return true;
+    case InstructionIndex::AnnotationToParent:
+      return true;
+    case InstructionIndex::AnnotationEmit:
+      return true;
+    default:
+      return false;
+  }
+}
+
 // Forward declaration for defining a circular structure
 #ifndef DOXYGEN
 struct Instruction;

test/evaluator/evaluator_test.cc

@@ -125,3 +125,14 @@ TEST(Evaluator, cross_2012_12_ref_2019_09_without_id) {
   const sourcemeta::core::JSON instance{"test"};
   EXPECT_TRUE(evaluator.validate(compiled_schema, instance));
 }
+
+TEST(Evaluator, is_annotation) {
+  EXPECT_TRUE(sourcemeta::blaze::is_annotation(
+      sourcemeta::blaze::InstructionIndex::AnnotationBasenameToParent));
+  EXPECT_TRUE(sourcemeta::blaze::is_annotation(
+      sourcemeta::blaze::InstructionIndex::AnnotationToParent));
+  EXPECT_TRUE(sourcemeta::blaze::is_annotation(
+      sourcemeta::blaze::InstructionIndex::AnnotationEmit));
+  EXPECT_FALSE(sourcemeta::blaze::is_annotation(
+      sourcemeta::blaze::InstructionIndex::AssertionFail));
+}