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Is there a reason why template-haskell doesn't provide QuasiQuoters corresponding to TH quotes [e| ... |], [d| ... |], etc.? A lot of packages provide QuasiQuoters that could be written as "[e| ... |] + extra stuff"; for example, a text interpolation library could be implemented as

-- the QuasiQuoter corresponding to [e| ... |]
eQQ :: QuasiQuoter

-- Interpolate: (let x = 1 in [text|x is: #{x}|]) == "x is: 1"
text :: QuasiQuoter
text =
  eQQ
    { quoteExp =
        appE [| concat |]
        . listE
        . map
          ( \case
            Left raw -> litE $ stringL raw
            Right interpolated -> quoteExp eQQ interpolated
          )
        . parse
    }

-- Parses "x is: #{x}" into [Left "x is: ", Right "x"]
parse :: String -> [Either String String]

Whereas currently, it'd have to pull in haskell-src-meta to parse the string.

As another example, we have a use case for easily writing lists of hlists:

rows =
  eQQ
    { quoteExp = listE . map (toHList . quoteExp eQQ) . lines
    }

-- generates [1 :& "hello" :& True :& Nil, 2 :& "world" :& False :& Nil]
[rows|
  [1, "hello", True]
  [2, "world", False]
|]

Today, the best way to do this without haskell-src-meta is to do

rows = listE . map toHList

$( rows
     [ [| [1, "hello", True] |]
     , [| [2, "world", False] |]
     ]
 )

I would imagine it's not straightforward, with the parsing of the TH quotes probably builtin to the compiler and not available at runtime, but if it's just a matter of breaking out the logic, I think it would be a big win on writing common QuasiQuoters