haskell - Why doesn't stack add packages to the ghc package database? -


i've decided try giving stack shot. i've installed , used install latest version of ghc. i've used stack install packages packages not visible ghc , when list packages ghc-pkg see packages i've installed through stack not there. why this? misunderstanding purpose of stack?

stack never touches global packages database. uses layered database approach

  1. global database - untouched
  2. packages in stackage snapshot installed snapshot database
  3. other packages installed locally per project

thus instead of polluting global database, packages installed in snapshot database(s), packages can shared. packages in stackage snapshots compatible (i.e. compile together), don't run cabal hell.

you can use stack ghci or stack ghc run corresponding commands package database configured.

the more precise explanation in stack wiki


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