cabal sandbox add-source directory-name not working

[p75213]

The command cabal sandbox add-source ..\folder is not working. When I issue the command cabal sandbox hc-pkg list it shows (no packages) for the local sandbox. If I issue the command: cabal install --only-dependencies it shows the following message:

All the requested packages are already installed:
Use --reinstall if you want to reinstall anyway.

I am using cabal version 1.24.0.0 on windows 7.

[23Skidoo]

Does your .cabal file include a dependency on the package in ..\folder?

[ezyang]

Just a friendly note: try out http://cabal.readthedocs.io/en/latest/nix-local-build-overview.html instead of sandboxes! You'll be pleasantly surprised.

[p75213]

Well I tried it again this morning and it worked. I haven't changed anything so I am at a loss to what was going on. Anyway all good now.
@ezyang Thanks for that. I will read it as soon as I get time.

[ezyang]

OK, I'll close this for now. Reopen if you see it again!