diff options
Diffstat (limited to 'haskell/cabal-lib.md')
| -rw-r--r-- | haskell/cabal-lib.md | 23 |
1 files changed, 3 insertions, 20 deletions
diff --git a/haskell/cabal-lib.md b/haskell/cabal-lib.md index acb2bf1..2504fc8 100644 --- a/haskell/cabal-lib.md +++ b/haskell/cabal-lib.md @@ -66,7 +66,7 @@ ghci> print "hi" ghci> ``` -I mean, that doesn't look good, doesn't it? +I mean, that doesn't look good, does it? And if that did not scare you enough, suppose that in the future, you want to use a newer version of `brick` and try to install that using `cabal install --lib brick` again. What you'll see is this: @@ -81,25 +81,8 @@ brick (I simulated the situation by installing an older version instead. I can't time-travel, unfortunately.) -Or suppose that you now also want to use another library, say `eigen`: - -``` -$ cabal install --lib eigen -Resolving dependencies... -Error: cabal: Could not resolve dependencies: -[__0] next goal: brick (user goal) -[__0] rejecting: -brick-1.10/installed-1f76dfaf75736c0f6e2a4a2cf992bb12da05f6bbc7985f9787547739947e4696 -(package is broken, missing dependency -bimap-0.5.0-2ee7565ca29f0edc78a3c8fe09c9eef36c96d08473660eec8a944cef16ac4d86) -[__0] trying: brick-1.10 -[__1] trying: vty-5.39 (dependency of brick) -... -... -``` - -The error message is much longer than this, but I cut it off to save some space. -Apparently it claims our installation of `brick` is actually broken, despite it working okay in `ghci`, but in any case this didn't work. +Another thing that would fail is trying to install a package that is incompatible with the versino of `brick` you have now "installed". +I don't have a good example for this post because I couldn't find a neat pair of incompatible packages that didn't have many other dependencies, but I hope you'll trust me that this will result in the well-known (to seasoned haskellers) cabal dependency resolution errors. ## What happened? |