ghc-singleton-bool from devel:languages:haskell:ghc-9.6.x project
Select Your Operating System
Add repository and install manually
For Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:haskell:ghc-9.6.x/Tumbleweed/devel:languages:haskell:ghc-9.6.x.repo zypper refresh zypper install ghc-singleton-bool