perf: introduce AST to avoid reparse

src/tokens/property-access-token.ts

@@ -0,0 +1,14 @@
+import { Token } from './token'
+import { WordToken } from './word-token'
+import { QuotedToken } from './quoted-token'
+import { TokenKind } from '../parser/token-kind'
+
+export class PropertyAccessToken extends Token {
+  constructor (
+    public variable: WordToken,
+    public props: (WordToken | QuotedToken | PropertyAccessToken)[],
+    end: number
+  ) {
+    super(TokenKind.PropertyAccess, variable.input, variable.begin, end, variable.file)
+  }
+}