Support Template Haskell Typed Quotes

[MHova]

This is probably a haskell-src-exts issue, but opening here anyway.

HLint is missing support for typed quotes, which has the [||...||] syntax. Currently HLint complains with a parse error.

[ndmitchell]

Thanks for the info - almost certainly one to report to haskell-src-exts. Do you have a small file using typed quotes that works as a valid GHC program (e.g. runhaskell on it works) but fails to parse? That's what the HSE people tend to use for reproducing bugs.

[ndmitchell]

Did this get into a real GHC release? I can't find it in the user manual.

[MHova]

Are you talking about a fix in haskell-src-exts to support Typed Quotes? Or the existence of the Typed Quotes feature at all in GHC?

[ndmitchell]

The feature in GHC. I would usually go to the GHC manual, grab a small sample, and then create an HSE ticket containing that. However, in this instance, googling just took me to the wiki.

[MHova]

Sorry for the ridiculously delayed response on this, but here's a simple example showing the problem.

{-# LANGUAGE TemplateHaskell #-}

module Example where

import Language.Haskell.TH (TExp, Q)

example :: Q (TExp String)
example = [|| "whatever" ||]

This code snippet compiles, but hlint can't parse the code because:

Example.hs:8:13: Error: Parse error
Found:
    example :: Q (TExp String)
  > example = [|| "whatever" ||]

Using GHC 7.10.3 and hlint 2.0.9.

[ndmitchell]

Thanks, reported upstream at haskell-suite/haskell-src-exts#383.

[ndmitchell]

Confirmed works with HEAD that doesn't use HSE for parsing, so fixed in the next release.