# E4153

Duplicated tag in `enum` with custom tag value.

For constant `enum`, where all constructors have no payload,
MoonBit supports customizing the integer representation of constructors:

```moonbit
enum Flag {
  A = 1
  B = 2
  C = 3
}
```

However, the tag of each constructor must be unique, otherwise this error will be reported.

## Erroneous example
```{literalinclude} /sources/error_codes/4153_error/top.mbt
:language: moonbit
```

## Suggestion

Use a unique tag for each constructor:

```{literalinclude} /sources/error_codes/4153_fixed/top.mbt
:language: moonbit
```