cabal: ... trying: directory-1.3.6.1 (user goal)

[jwaldmann]

There is some cabal env-file hell going on. I can install with

cabal install tidal safe-tidal --lib # installs	libraries
cabal install safe-tidal  --constraint 'tidal==1.4.9' # installs executable

but then I cannot re-install:

cabal: Could not resolve dependencies:
[__0] trying: directory-1.3.6.1 (user goal)
[__1] next goal: ghc (user goal)
[__1] rejecting: ghc-8.8.3/installed-8.8.3 (conflict: directory==1.3.6.1, ghc
=> directory==1.3.6.0/installed-1.3.6.0)

The work-around is to remove directory and process lines from ~/.ghc/x86_64-linux-8.8.3/environments/default and then try again.