module support

object/environment.go

@@ -1,5 +1,7 @@
 package object
 
+import "unicode"
+
 func NewEnclosedEnvironment(outer *Environment) *Environment {
 	env := NewEnvironment()
 	env.outer = outer
@@ -28,3 +30,18 @@ func (e *Environment) Set(name string, val Object) Object {
 	e.store[name] = val
 	return val
 }
+
+// ExportedHash returns a new Hash with the names and values of every publicly
+// exported binding in the environment. That is every binding that starts with a
+// capital letter. This is used by the module import system to wrap up the
+// evaluated module into an object.
+func (e *Environment) ExportedHash() *Hash {
+	pairs := make(map[HashKey]HashPair)
+	for k, v := range e.store {
+		if unicode.IsUpper(rune(k[0])) {
+			s := &String{Value: k}
+			pairs[s.HashKey()] = HashPair{Key: s, Value: v}
+		}
+	}
+	return &Hash{Pairs: pairs}
+}