Re: [Haskell-cafe] Coercible between data A a b = A a b and (a, b)

Two data types are `Coercible` (as in Data.Coerce) if their representation in memory is the same: they are representiationally equivalent You ask for looser structural isomorphism, consider e.g. data B b = B {-# UNPACK #-} !Int b and (Int, b) The values of these types have quite different representation/memory layout. - Oleg

On 25 Feb 2019, at 16.38, Georgi Lyubenov wrote:

Greetings!

Is there any reason behind/what is the reason behind ``` data A a b = A a b ``` and ``` (a, b) ```

not being coercible?

And in general all n-ary constructors not being coercible to one another?

Thanks in advance!

======= Georgi _______________________________________________ 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.