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kotlinlang

I have two enums

```enum class Entity {
   PROJECT, WORKSPACE, ...```
```enum class Access {
   UPDATE, REMOVE, GRANT, ...```
and i want to write an annotation

`ProjectPermission("$PROJECT.$UPDATE", "$PROJECT.$READ")`

```@Repeatable
@MustBeDocumented
@Target(AnnotationTarget.FUNCTION)
@Retention(AnnotationRetention.RUNTIME)
annotation class ProjectPermission(vararg val permission: String)```
Problem is, the annotation requires a constant, is there a way to convert the String template containing the enums to a constant?

The other alternative is to write annotations `@ProjectPermission(PROJECT, UPDATE)`, but i can only have one @ProjectPermission on my method with Runtime retention, so the string route allows for more permissions

There is a chance that rephrasing the problem more precisely would help people help you.

You can’t concatenate expressions because the compiler will accept only a verifiable compile-time constant, otherwise it can’t determine it. The other solution to use enum values would be the best one. Why using @Repeatable doesn’t solve your problem?

if i stack multiple @ProjectPermission on a function, Kotlin complains that it can't repeat @ProjectPermission unless it's Source Retention

```Repeatable annotations with non-SOURCE retention are not yet supported```
I need these to be retained in runtime so that i can pick them up via reflection, which source retention doesn't allow

Oh I see… didn’t know this detail. Then you can do this only with annotation arguments:
```@Retention(AnnotationRetention.RUNTIME)
annotation class Permission(val entity: Entity, val access: Access)

@MustBeDocumented
@Target(AnnotationTarget.FUNCTION)
@Retention(AnnotationRetention.RUNTIME)
annotation class ProjectPermission(vararg val permission: Permission)

// then use it on a function:
@ProjectPermission(
        Permission(Entity.PROJECT, Access.UPDATE),
        Permission(Entity.PROJECT, Access.GRANT)
        // etc
)
fun annotated() {
}```

Yes it works, don’t worry. You’re welcome!