What I am trying to do is pretty basic. Given an object, and without caring about the properties names, I want to ensure all its values to be of a certain type. 

Therefore I have something like the following code:

```
// @flow

type DynamicStructure = {
    [string]: number
}

const key: string = "someKey"
const someStructure: DynamicStructure = {
    [key]: "invalid, should be a number"
}

```

The weird thing is that I am getting "no errors!" after applying Flow on the code above, which is clearly wrong. You can verify this behaviour on the [Flow REPL](https://flow.org/try/#0PTAEAEDMBsHsHcBQiAuBPADgU1AETQHYCGAtgJYDGAyigE4CuFK9tOAvKAN6ICQA2gGc6ZAgHMAugC5QBeiQBGWWogC+yCrAJDQAayxppQ2iNGgOAIgGwSWANL7ziDVpSgrNmgyYss0-MXJqOkZmVjMuXj49NClQcxEANyJoMgATABo3AAtYemhU0EVQIhk5RVpHNSA)

On the other hand, when I don't use dynamic accessors for the object everything work as expected. For example for the following code I get the expected errors:

```
// @flow

type DynamicStructure = {
    [string]: number
}

const someStructure: DynamicStructure = {
    "someKey": "invalid, should be a number"
}

```

Am I doing something wrong? or is this a Flow issue?

Thanks in advance.