[Haskell-beginners] data type design question
jason.dusek at gmail.com
Wed Jul 30 15:28:36 EDT 2008
A data declaration _defines_ type constructors. You describe
what types those constructors can accept, so this:
= TString String
| TInt Integer
| TList [T]
| TDict [(TString, T)]
actually doesn't make any sense -- the list holds what? Holds
tuples of `TString` and `T`. What type is `TString` ? It's not
a type, it's a constructor! So you need to make it a type.
Also, it is not clear to me why the `TDict` can not just map
`String`s to `T`s -- if you get a `TString` in the course of
parsing, you can unwrap it.
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