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@@ -0,0 +1,30 @@
+```ts
+// a(b)
+type Call = ['()', Exp, Exp]
+
+// a.bc
+type Dot = ['.', Exp, Index, PropertyLambda]
+
+// a?.bc
+type OptionDot = ['?.', Exp, Index, OptionPropertyLambda]
+
+// a?(b)c
+type OptionCall = ['?.()', Exp, Exp, OptionLambda]
+
+type PropertyLambda =
+    | null
+    | ['()', Exp]
+    | ['?.()', Exp, OptionLambda]
+
+type OptionLambda =
+    | null
+    | ['()', Exp, OptionLambda]
+    | ['.', Index, OptionPropertyLambda]
+
+type OptionPropertyLambda =
+    | null
+    | ['()', Exp, OptionLambda]
+    | ['.', Index, OptionPropertyLambda]
+    | ['?.()', Exp, OptionLambda]
+    | ['!()', Exp]
+```