The project designs a symbolic execution engine for quantum programs based on Qafny.

Also may present as a lexer issue on a UTF-8 character.

This is a strange issue, mostly due to the long-standing lack of support for UTF-8 on Windows. A potential fix is enabling the new UTF-8 option in Windows settings. Go to the language settings, click Administrative language settings, then Change system locale… and tick the Beta: Use Unicode UTF-8 for worldwide language support option. This will require a restart. If that doesn't work, here are some resources that could help:

• Using UTF-8 in the Windows Terminal
• terminal haskell package
• UTF-8 input/output in from Haskell in Windows
• Haskell with UTF-8

Don't forget to enable the haskell option "OverloadedStrings".

GHCi:

ghci> :set -XOverloadedStrings

Haskell Source:

{-# LANGUAGE OverloadedStrings #-}