Hi I've just updated cabal to the latest version by the command
cabal update
and
cabal install cabal-install
Then it returns
Installed cabal-install-1.22.2.0
Updating documentation index /MyPath
I want to use alex and happy. Sorry I'm very new to it.. When I tried to issue alex in ghci by the line
alex wordcount.x
It returns
Not in scope: ‘alex’
Perhaps you meant ‘lex’ (imported from Prelude)
I searched online for this and I found a webpage saying that I should first check the version of them by
cabal configure -v | grep -e alex -e happy
But I got this line
cabal: No cabal file found.
Please create a package description file <pkgname>.cabal
Could anyone help me with this problem?
Once you install cabal you can install other packages.
So, to install the Alex package, you'll do cabal install alex. Then I see that you tried to invoke Alex in GHCi, but that's not correct, since alex is a program. You have to invoke it from the terminal.