On Mon, Apr 23, 2012 at 9:58 AM, Yitzchak Gale
Jeremy Shaw wrote:
I have often wished for something like: {-# LANGUAGE StringLiteralsAs Text #-} where all string literals like: f = "foo" would be translated to: f = (fromString "foo" :: Text)
Agreed, I would also really like this.
I find that OverloadedStrings is too general and causes ambiguous type errors. Additionally, I seldom find that I have more than one type of string literal per file. Things tend to be all String, all Text, etc. So, if I could just pick a concrete type for all the string literals in my file, I would be happy.
In addition, OverloadedStrings is unsound. Library authors can, and do, write unsafe implementations of IsString that cause syntax errors to be caught only at run time instead of at compile time. That is the opposite of one of the most important things we are trying to accomplish by using Haskell instead of, say, some dynamically typed language.
Greg Weber wrote:
You can default a String. So this compiles just fine:
{-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE ExtendedDefaultRules #-} import Data.Text as T default (T.Text)
No, I do not want string literals to be polymorphic, even if there is some kind of defaulting. I want them to be monomorphic, as they always have been. But I still want to be able to specify to the compiler somehow that the monomorphic type for string literals in a particular module should be something other than String.
Thanks, Yitz
Hi Yitz, I very much agree with you. However, when we complain about something essentially we are asking others to prioritize it ahead of other things. I don't think any more visibility of this issue is going to improve its prioritization. I suspect your only way forward right now is to start implementing something yourself.