Haskell prime breaks highlighting

[Fresheyeball]

Describe the bug
In the Haskell language the ' character may be used in a variable name, and frequently is (pronounced "prime").

foo :: Int -> Int
foo x' = x' + 1

This case causes the highlighting to treat the entire rest of the file as a giant string, since there is no closing '.

Other use cases for ' appear to work, including describing a Char

letterC :: Char
letterC = 'C'

and promoted types

data Foo = Bar
toUnit :: Proxy 'Bar -> ()
toUnit _ = ()

but not in variable names.

To Reproduce
This effect can be seen in this file here:
https://gitlab.com/fresheyeball/Shpadoinkle/-/blob/master/examples/servant-crud/View.hs#L77

Expected behavior
The single tick is not treated as the start of a string. Note the syntax highlighting is correct on GitHub, which does not use Rouge. Here is the same file in a gist for comparison:
https://gist.github.com/Fresheyeball/495f2f68718cc1a539a00b7d36a4e4fd

[pyrmont]

@Fresheyeball When ' is used to describe a Char, are the number of characters used in the source code always 1? Can you, for example, have this:

newline :: Char
newline = '\n'

[Fresheyeball]

@pyrmont the newline char example you posted is legal Haskell