In the following code:

type color = [`Red | `Blue | `Green | `Black | `White]

let color_index c = match c with

| `Red -> 1

| `Blue -> 2

| `Green -> 3

| `Black -> 4

| `White -> 5

type value = [`Red | `Blue | `Green | `Missing]

type state = Color of int | Missing

let state_of_value v = match v with

| `Red -> Color (color_index `Red)

| `Blue -> Color (color_index `Blue)

| `Green -> Color (color_index `Green)

| `Missing -> Missing

is there any way to write the last function as

let state_of_value v = match v with

| `Red | `Blue | `Green -> ?????

| `Missing -> Missing

martin