better sem analysis

index.cm

@@ -22,6 +22,7 @@ var index_ast = function(ast, tokens, filename) {
   var references = []
   var call_sites = []
   var exports_list = []
+  var intrinsic_refs = []
   var node_counter = 0
   var fn_map = {}
   var _i = 0
@@ -147,6 +148,29 @@ var index_ast = function(ast, tokens, filename) {
 
     nid = next_id()
 
+    // this keyword
+    if (node.kind == "this") {
+      references[] = {
+        node_id: nid,
+        name: "this",
+        symbol_id: null,
+        span: make_span(node),
+        enclosing: enclosing,
+        ref_kind: "read"
+      }
+      return
+    }
+
+    // Capture intrinsic refs with positions (intrinsics lack function_nr).
+    if (node.kind == "name" && node.name != null && node.intrinsic == true) {
+      intrinsic_refs[] = {
+        node_id: nid,
+        name: node.name,
+        span: make_span(node),
+        enclosing: enclosing
+      }
+    }
+
     // Name reference — has function_nr when it's a true variable reference.
     if (node.kind == "name" && node.name != null && node.function_nr != null) {
       if (node.intrinsic != true) {
@@ -208,6 +232,17 @@ var index_ast = function(ast, tokens, filename) {
         }
       }
 
+      // Capture intrinsic callee refs (e.g., print, length).
+      if (node.expression != null && node.expression.kind == "name" &&
+          node.expression.intrinsic == true && node.expression.name != null) {
+        intrinsic_refs[] = {
+          node_id: nid,
+          name: node.expression.name,
+          span: make_span(node.expression),
+          enclosing: enclosing
+        }
+      }
+
       // Walk callee expression (skip name — already recorded above).
       if (node.expression != null && node.expression.kind != "name") {
         walk_expr(node.expression, enclosing, false)
@@ -596,6 +631,7 @@ var index_ast = function(ast, tokens, filename) {
     imports: imports,
     symbols: symbols,
     references: references,
+    intrinsic_refs: intrinsic_refs,
     call_sites: call_sites,
     exports: exports_list,
     reverse_refs: reverse