diff --git a/src/main/grammar/main.bnf b/src/main/grammar/main.bnf
index f2d6de1..a1d084a 100644
--- a/src/main/grammar/main.bnf
+++ b/src/main/grammar/main.bnf
@@ -1,6 +1,7 @@
 {
     generate=[token-case="as-is" element-case="as-is"]
     parserClass="me.zhouxi.slint.lang.parser.SlintParser"
+    parserUtilClass="me.zhouxi.slint.lang.psi.SlintParserUtil"
     implements="me.zhouxi.slint.lang.psi.SlintPsiElement"
     extends="me.zhouxi.slint.lang.psi.impl.SlintPsiElementImpl"
     elementTypeHolderClass="me.zhouxi.slint.lang.psi.SlintTypes"
@@ -10,57 +11,58 @@
     psiImplClassSuffix="Impl"
     psiPackage="me.zhouxi.slint.lang.psi"
     psiImplPackage="me.zhouxi.slint.lang.psi.impl"
-    tokens=[
-        Comma = ","
-        FatArrow = "=>"
-        DoubleArrow = "<=>"
-        PlusEqual = "+="
-        MinusEqual = "-="
-        StarEqual = "*="
-        DivEqual = "/="
-        LessEqual = "<="
-        GreaterEqual = ">="
-        EqualEqual = "=="
-        NotEqual = "!="
-        ColonEqual = ":="
-        Arrow = "->"
-        OrOr = "||"
-        AndAnd = "&&"
-        LBrace = "{"
-        RBrace = "}"
-        LParent = "("
-        RParent = ")"
-        LAngle = "<"
-        RAngle = ">"
-        LBracket = "["
-        RBracket = "]"
-        Plus = "+"
-        Minus = "-"
-        Star = "*"
-        Div = "/"
-        Equal = "="
-        Colon = ":"
-        Comma = ","
-        Semicolon = ";"
-        Bang = "!"
-        Dot = "."
-        Question = "?"
-        Dollar = "$"
-        At = "@"
-        Pipe = "|"
-        Percent = "%"
-        Whitespace = "regexp:(\s+)"
-        NumberLiteral = "regexp:\d+(\.(\d+)?)?([a-z]+|%)?"
-        Identifier = "regexp:^[a-zA-Z_][A-Za-z0-9\-_]*"
-        ColorLiteral = "regexp:#([a-zA-Z0-9]+)"
-        StringLiteral  = 'regexp:(^"[^"\r\n]*")'
-        LineComment = 'regexp:^//[^\r\n]*'
-        BlockComment = 'regexp:/\*[\s\S]*?\*/'
-
-    ]
     extends(".*Expression")=Expression
-    implements(".*Keyword")=["me.zhouxi.slint.lang.psi.keyword.SlintPsiKeywordIdentifier"]
-    mixin(".*Keyword")="me.zhouxi.slint.lang.psi.keyword.SlintPsiKeywordIdentifierImpl"
+    implements(".*Keyword")=["me.zhouxi.slint.lang.psi.SlintPsiKeyword"]
+    extends(".*Keyword")="me.zhouxi.slint.lang.psi.SlintPsiKeyword.Impl"
+    elementTypeFactory(".*Keyword")="me.zhouxi.slint.lang.psi.SlintPsiKeyword.type"
+    tokens=[
+            Comma = ","
+            FatArrow = "=>"
+            DoubleArrow = "<=>"
+            PlusEqual = "+="
+            MinusEqual = "-="
+            StarEqual = "*="
+            DivEqual = "/="
+            LessEqual = "<="
+            GreaterEqual = ">="
+            EqualEqual = "=="
+            NotEqual = "!="
+            ColonEqual = ":="
+            Arrow = "->"
+            OrOr = "||"
+            AndAnd = "&&"
+            LBrace = "{"
+            RBrace = "}"
+            LParent = "("
+            RParent = ")"
+            LAngle = "<"
+            RAngle = ">"
+            LBracket = "["
+            RBracket = "]"
+            Plus = "+"
+            Minus = "-"
+            Star = "*"
+            Div = "/"
+            Equal = "="
+            Colon = ":"
+            Comma = ","
+            Semicolon = ";"
+            Bang = "!"
+            Dot = "."
+            Question = "?"
+            Dollar = "$"
+            At = "@"
+            Pipe = "|"
+            Percent = "%"
+            Whitespace = "regexp:(\s+)"
+            NumberLiteral = "regexp:\d+(\.(\d+)?)?([a-z]+|%)?"
+            Identifier = "regexp:^[a-zA-Z_][A-Za-z0-9\-_]*"
+            ColorLiteral = "regexp:#([a-zA-Z0-9]+)"
+            StringLiteral  = 'regexp:(^"[^"\r\n]*")'
+            LineComment = 'regexp:^//[^\r\n]*'
+            BlockComment = 'regexp:/\*[\s\S]*?\*/'
+    
+        ]
 }
 //
 Document ::= DocumentElement*