On Feb 1, 2021, at 4:51 AM, Sylvain Henry <sylvain@haskus.fr> wrote:

Hi,

I have the following kind of template haskell code:

module Foo where
foo :: String -> Name -> Q [Dec]
foo str name = return []

module Bar where
bar :: String
bar = "whatever"

module FooBar where
import Foo
import Bar
foo bar 'bar

It works great as in `foo` I can use both bar's Name and bar's value computed at compile time.

But it's unsafe for my purpose because a user could call: `foo "fakeBarValue"  'bar`

So the question is: is there a way to write `foo` so that it can only be used safely?

If not, I guess it could be possible to add a new kind of quote to TH, something like:

data Named a = Named Name a -- constructor not exported so that Named values can't be forged by users.

[namedValue||bar||] :: Named String -- new quote

What do you think?

Thanks,
Sylvain

_______________________________________________
Haskell-Cafe mailing list
To (un)subscribe, modify options or view archives go to:
http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
Only members subscribed via the mailman list are allowed to post.