1 files changed, 39 insertions, 0 deletions
diff --git a/compiler/plugins/locals.nim b/compiler/plugins/locals.nim
new file mode 100644
index 000000000..d3046cd65
--- /dev/null
+++ b/compiler/plugins/locals.nim
@@ -0,0 +1,39 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2015 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## The builtin 'system.locals' implemented as a plugin.
+
+import ".." / [ast, astalgo,
+  magicsys, lookups, semdata, lowerings]
+
+proc semLocals*(c: PContext, n: PNode): PNode =
+  var counter = 0
+  var tupleType = newTypeS(tyTuple, c)
+  result = newNodeIT(nkTupleConstr, n.info, tupleType)
+  tupleType.n = newNodeI(nkRecList, n.info)
+  let owner = getCurrOwner(c)
+  # for now we skip openarrays ...
+  for scope in localScopesFrom(c, c.currentScope):
+    for it in items(scope.symbols):
+      if it.kind in skLocalVars and
+          it.typ.skipTypes({tyGenericInst, tyVar}).kind notin
+            {tyVarargs, tyOpenArray, tyTypeDesc, tyStatic, tyUntyped, tyTyped, tyEmpty}:
+
+        if it.owner == owner:
+          var field = newSym(skField, it.name, c.idgen, owner, n.info)
+          field.typ = it.typ.skipTypes({tyVar})
+          field.position = counter
+          inc(counter)
+
+          tupleType.n.add newSymNode(field)
+          addSonSkipIntLit(tupleType, field.typ, c.idgen)
+
+          var a = newSymNode(it, result.info)
+          if it.typ.skipTypes({tyGenericInst}).kind == tyVar: a = newDeref(a)
+          result.add(a)