Resolving dependencies... Configuring mtl-2.2.1... Configuring text-1.2.2.1... Building text-1.2.2.1... Building mtl-2.2.1... Installed mtl-2.2.1 Installed text-1.2.2.1 Configuring parsec-3.1.11... Building parsec-3.1.11... Installed parsec-3.1.11 Configuring CPL-0.0.5... Building CPL-0.0.5... Failed to install CPL-0.0.5 Build log ( /home/builder/.cabal/logs/CPL-0.0.5.log ): cabal: Entering directory '/tmp/cabal-tmp-20500/CPL-0.0.5' Configuring CPL-0.0.5... Building CPL-0.0.5... Preprocessing executable 'cpl' for CPL-0.0.5... src/Type.hs:1:12: warning: -fglasgow-exts is deprecated: Use individual extensions instead src/Subst.hs:1:12: warning: -fglasgow-exts is deprecated: Use individual extensions instead src/FE.hs:1:12: warning: -fglasgow-exts is deprecated: Use individual extensions instead [ 1 of 17] Compiling Variance ( src/Variance.hs, dist/build/cpl/cpl-tmp/Variance.o ) [ 2 of 17] Compiling ParserUtils ( src/ParserUtils.hs, dist/build/cpl/cpl-tmp/ParserUtils.o ) [ 3 of 17] Compiling Funct ( src/Funct.hs, dist/build/cpl/cpl-tmp/Funct.o ) [ 4 of 17] Compiling CDT[boot] ( src/CDT.hs-boot, dist/build/cpl/cpl-tmp/CDT.o-boot ) [ 5 of 17] Compiling FE ( src/FE.hs, dist/build/cpl/cpl-tmp/FE.o ) [ 6 of 17] Compiling Subst ( src/Subst.hs, dist/build/cpl/cpl-tmp/Subst.o ) [ 7 of 17] Compiling Type ( src/Type.hs, dist/build/cpl/cpl-tmp/Type.o ) [ 8 of 17] Compiling CDT ( src/CDT.hs, dist/build/cpl/cpl-tmp/CDT.o ) src/CDT.hs:202:9: error: • Non type-variable argument in the constraint: Subst.FEs (GenFE t) (Use FlexibleContexts to permit this) • When checking the inferred type f :: forall t t1. Subst.FEs (GenFE t) => (t1, GenType t) -> Bool In an equation for ‘isUnconditioned’: isUnconditioned = all f natDecls where f (_, dom :-> cod) = case t of { LeftObject -> 0 `notElem` tv dom RightObject -> 0 `notElem` tv cod } In an equation for ‘mkCDT’: mkCDT t functName functArity factName natDecls = object where object = CDT {objectType = t, nats = nats, nNats = length (natDecls), isUnconditioned = isUnconditioned, functName = functName, functVariance = vs, functArity = functArity, factName = factName, factParams = map snd natDecls, factDestType = factDestType} vs = map joinL . transpose . map f $ natDecls where f (_, dom :-> cod) = zipWith g (tail (variance (CFE (1 + functArity) dom))) (tail (variance (CFE (1 + functArity) cod))) g = ... factDestType = case t of { LeftObject -> a :-> b RightObject -> b :-> a } where a = Ap object ... b = Var 0 nats = zipWith f natDecls [0 .. ] where f (name, declType@(dom :-> cod)) idx = nat where ... .... cabal: Leaving directory '/tmp/cabal-tmp-20500/CPL-0.0.5' cabal: Error: some packages failed to install: CPL-0.0.5 failed during the building phase. The exception was: ExitFailure 1