wrap the prev/next comment members for future upgrades

source/md.c

@@ -508,10 +508,10 @@ static MD_Node _md_nil_node =
     MD_ZERO_STRUCT,        // string
     MD_ZERO_STRUCT,        // raw_string
     0xdeadffffffffffull,   // string_hash
-    MD_ZERO_STRUCT,        // prev_comment
-    MD_ZERO_STRUCT,        // next_comment
     0,                     // at
     &_md_nil_node,         // ref_target
+    MD_ZERO_STRUCT,        // prev_comment
+    MD_ZERO_STRUCT,        // next_comment
 };
 
 //~ Arena Functions
@@ -2839,12 +2839,23 @@ MD_TagCountFromNode(MD_Node *node)
 MD_FUNCTION_IMPL MD_Node *
 MD_NodeFromReference(MD_Node *node)
 {
+    MD_u64 safety = 100;
+    for(; safety > 0 && node->kind == MD_NodeKind_Reference;
+        safety -= 1, node = node->ref_target);
     MD_Node *result = node;
-    while(result->kind == MD_NodeKind_Reference)
+    return(result);
-    {
-        result = result->ref_target;
 }
-    return result;
+
+MD_FUNCTION_IMPL MD_String8
+MD_PrevCommentFromNode(MD_Node *node)
+{
+    return(node->prev_comment);
+}
+
+MD_FUNCTION_IMPL MD_String8
+MD_NextCommentFromNode(MD_Node *node)
+{
+    return(node->next_comment);
 }
 
 //~ Error/Warning Helpers

source/md.h

@@ -605,18 +605,19 @@ struct MD_Node
     MD_String8 raw_string;
     MD_u64 string_hash;
     
-    // Comments.
-    // TODO(rjf): @node_comments these are pretty under-powered... should they
-    // just be nodes, maybe? Would that allow for some cool stuff, like comment
-    // hierarchies?
-    MD_String8 prev_comment;
-    MD_String8 next_comment;
-    
     // Source code location information.
     MD_u64 offset;
     
     // Reference.
     MD_Node *ref_target;
+    
+    
+    // Comments.
+    // @usage prev_comment/next_comment should be considered "hidden". Rely on
+    // the functions MD_PrevCommentFromNode/MD_NextCommentFromNode to access
+    // these. Directly access to these is likely to break in a future version.
+    MD_String8 prev_comment;
+    MD_String8 next_comment;
 };
 
 //~ Code Location Info.
@@ -1091,6 +1092,9 @@ MD_FUNCTION MD_i64     MD_ChildCountFromNode(MD_Node *node);
 MD_FUNCTION MD_i64     MD_TagCountFromNode(MD_Node *node);
 MD_FUNCTION MD_Node *  MD_NodeFromReference(MD_Node *node);
 
+MD_FUNCTION MD_String8 MD_PrevCommentFromNode(MD_Node *node);
+MD_FUNCTION MD_String8 MD_NextCommentFromNode(MD_Node *node);
+
 // NOTE(rjf): For-Loop Helpers
 #define MD_EachNode(it, first) MD_Node *it = (first); !MD_NodeIsNil(it); it = it->next
 #define MD_EachNodeRef(it, first) MD_Node *it##_r = (first), *it = MD_NodeFromReference(it##_r); \