ihaskell/wrapper.nix: unify ihaskellEnv and ihaskell

Having both `ihaskell` and `ihaskellEnv` is redundant, and might even
cause problems if the two differ somehow.

pkgs/development/tools/haskell/ihaskell/wrapper.nix

@@ -1,4 +1,4 @@
-{ stdenv, writeScriptBin, makeWrapper, buildEnv, haskell, ghcWithPackages, ihaskell, jupyter, packages }:
+{ stdenv, writeScriptBin, makeWrapper, buildEnv, haskell, ghcWithPackages, jupyter, packages }:
 let
   ihaskellEnv = ghcWithPackages (self: [
     self.ihaskell
@@ -9,8 +9,8 @@ let
   ihaskellSh = writeScriptBin "ihaskell-notebook" ''
     #! ${stdenv.shell}
     export GHC_PACKAGE_PATH="$(echo ${ihaskellEnv}/lib/*/package.conf.d| tr ' ' ':'):$GHC_PACKAGE_PATH"
-    export PATH="${stdenv.lib.makeBinPath ([ ihaskell ihaskellEnv jupyter ])}"
-    ${ihaskell}/bin/ihaskell install -l $(${ihaskellEnv}/bin/ghc --print-libdir) && ${jupyter}/bin/jupyter notebook
+    export PATH="${stdenv.lib.makeBinPath ([ ihaskellEnv jupyter ])}"
+    ${ihaskellEnv}/bin/ihaskell install -l $(${ihaskellEnv}/bin/ghc --print-libdir) && ${jupyter}/bin/jupyter notebook
   '';
 in
 buildEnv {

pkgs/top-level/all-packages.nix

@@ -2687,7 +2687,7 @@ with pkgs;
 
 
   ihaskell = callPackage ../development/tools/haskell/ihaskell/wrapper.nix {
-    inherit (haskellPackages) ihaskell ghcWithPackages;
+    inherit (haskellPackages) ghcWithPackages;
 
     jupyter = python3.withPackages (ps: [ ps.jupyter ps.notebook ]);