diff --git a/constant/provider/interface.go b/constant/provider/interface.go
index 08cd1926..7f1bda42 100644
--- a/constant/provider/interface.go
+++ b/constant/provider/interface.go
@@ -2,7 +2,6 @@ package provider
 
 import "C"
 import (
-	"errors"
 	"github.com/Dreamacro/clash/component/trie"
 	"github.com/Dreamacro/clash/constant"
 )
@@ -108,9 +107,6 @@ type RuleProvider interface {
 }
 
 var (
-	parse = func(ruleType, rule string, params []string) (constant.Rule, error) {
-		return nil, errors.New("unimplemented function")
-	}
 	ruleProviders = map[string]*RuleProvider{}
 )
 
@@ -122,7 +118,7 @@ type ruleSetProvider struct {
 	count          int
 	DomainRules    *trie.DomainTrie
 	IPCIDRRules    *trie.IpCidrTrie
-	ClassicalRules []constant.Rule
+	ClassicalRules []C.Rule
 }
 
 type RuleSetProvider struct {