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Resolving dependencies...
Starting     grid-7.8.10
Building     grid-7.8.10
Completed    grid-7.8.10
Starting     som-10.1.1
Building     som-10.1.1
Failed to install som-10.1.1
Build log ( /home/builder/.cabal/logs/ghc-8.6.1/som-10.1.1-Dg63X2g8OeD7oJXit2XLZq.log ):
cabal: Entering directory '/tmp/cabal-tmp-2072/som-10.1.1'
Configuring som-10.1.1...
Preprocessing library for som-10.1.1..
Building library for som-10.1.1..
[ 1 of 11] Compiling Data.Datamining.Clustering.Classifier ( src/Data/Datamining/Clustering/Classifier.hs, dist/build/Data/Datamining/Clustering/Classifier.o )
[ 2 of 11] Compiling Data.Datamining.Clustering.DSOMInternal ( src/Data/Datamining/Clustering/DSOMInternal.hs, dist/build/Data/Datamining/Clustering/DSOMInternal.o )
[ 3 of 11] Compiling Data.Datamining.Clustering.DSOM ( src/Data/Datamining/Clustering/DSOM.hs, dist/build/Data/Datamining/Clustering/DSOM.o )
[ 4 of 11] Compiling Data.Datamining.Clustering.SGM2Internal ( src/Data/Datamining/Clustering/SGM2Internal.hs, dist/build/Data/Datamining/Clustering/SGM2Internal.o )
[ 5 of 11] Compiling Data.Datamining.Clustering.SGM2 ( src/Data/Datamining/Clustering/SGM2.hs, dist/build/Data/Datamining/Clustering/SGM2.o )
[ 6 of 11] Compiling Data.Datamining.Clustering.SGMInternal ( src/Data/Datamining/Clustering/SGMInternal.hs, dist/build/Data/Datamining/Clustering/SGMInternal.o )
[ 7 of 11] Compiling Data.Datamining.Clustering.SGM ( src/Data/Datamining/Clustering/SGM.hs, dist/build/Data/Datamining/Clustering/SGM.o )
[ 8 of 11] Compiling Data.Datamining.Clustering.SOMInternal ( src/Data/Datamining/Clustering/SOMInternal.hs, dist/build/Data/Datamining/Clustering/SOMInternal.o )

src/Data/Datamining/Clustering/SOMInternal.hs:134:10: error:
    • Illegal nested constraint ‘G.Grid (GM.BaseGrid gm p)’
      (Use UndecidableInstances to permit this)
    • In the instance declaration for ‘GM.GridMap (SOM t d gm x k) p’
    |
134 | instance (F.Foldable gm, GM.GridMap gm p, G.Grid (GM.BaseGrid gm p))
    |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...
cabal: Leaving directory '/tmp/cabal-tmp-2072/som-10.1.1'
cabal: Error: some packages failed to install:
som-10.1.1-Dg63X2g8OeD7oJXit2XLZq failed during the building phase. The
exception was:
ExitFailure 1