pufuwozu/roy — Issue #77: Disallow identically named type parameters
Author: eegg
Created: 2011-12-13 01:10:33+00:00
State: open

The Roy code

```haskell
data Maybe a a = Nothing | Just a
```

generates (0.1.3) the JS

```javascript
var Nothing = function(){};
var Just = function(a){this._0 = a};
```

where it should generate a compile error, like GHC: "Repeated type variable "a" on left hand side"