foo :: Int -> Int
foo x =
    let z = y
        y = x
     in z + 100

bar :: Int -> Int
bar x =
    let z = y
        y = x
     in z
            + 100

inlineComment :: Int -> Int
inlineComment =
    let {- join -} go = case () of
                    () -> undefined
     in go

implicitParams :: HasCallStack => Int
implicitParams =
    let ?cs = ?callstack
     in foo cs

sitting =
    foo $
        let x = 20
         in x