wren ng thornton
That's what SORF does: the String Kind
No proposal is using a _type_-level string. Barney's confused you.
I was under the impression that all the working proposals were using the Has class, ...
Yes, but:
a la:
someFunction :: Has "name" a => a -> Foo someFunction x = ... (name x) ...
No! Have you read any of the proposals? Which bit of your anatomy did you use? Note that that syntax is not valid H98. Also note that the `Has` class uses three arguments, and in a different sequence to what you show. That syntax (with 3 args present) turns up in two places: 1. SPJ's SORF proposal 2. Barney Hilken's postings. Please ignore them, is all I can say. Neither I nor SPJ had anything to do with them. The DORF syntax is: someFunction :: Has r Proxy_name t => r -> t I prefer the sugar, which is the same for SORF and DORF (SPJ invented it, I stole it unashamedly): someFunction :: r{ name :: t } => r -> t The difference between the desugarring is crucial: - SORF desugars to a String Kind -- hence Has r "name" t => ... the "name" in quotes represents a String Kind - DORF desugars to a (proxy) type, not some new-fangled Kind Has r Proxy_name t => ... That is H98 (with multi-param type classes). I propose we use the sugar, so that the implementor can decide how to, um, implement.
modulo the debate about the value-level syntax for records, and modulo the debate about whether Has should be exposed to users or hidden inside GHC. Is this no longer the case?
Was _never_ the case, you've been paying too much attention to the wrong postings. Look at the wiki pages: that's why I posted it. I repeat: nobody is using a "type-level string". You (or someone) is making it up. This is beginning to exasperate me. Read the wikis: can you see "type-level string"? Certainly not on the DORF pages, I'm pretty sure not on the SORF pages. If you find it somewhere else, tell me and I'll get it changed. AntC