Implemented variable scopes

src/build/core/state.go

@@ -12,7 +12,7 @@ import (
 // state is the data structure we embed in each function to preserve compilation state.
 type state struct {
 	err             error
-	variables       map[string]*Variable
+	scopes          []Scope
 	functions       map[string]*Function
 	registerHistory []uint64
 	finished        chan struct{}