Resolving dependencies... Configuring ObjectName-1.1.0.1... Configuring fixed-0.2.1.1... Building fixed-0.2.1.1... Building ObjectName-1.1.0.1... Installed ObjectName-1.1.0.1 Configuring half-0.2.2.3... Configuring mtl-2.2.1... Installed fixed-0.2.1.1 Building half-0.2.2.3... Building mtl-2.2.1... Configuring random-1.1... Installed half-0.2.2.3 Building random-1.1... Configuring primitive-0.6.1.0... Installed mtl-2.2.1 Building primitive-0.6.1.0... Configuring stm-2.4.4.1... Installed random-1.1 Building stm-2.4.4.1... Configuring utf8-string-1.0.1.1... Installed stm-2.4.4.1 Configuring text-1.2.2.1... Installed primitive-0.6.1.0 Building utf8-string-1.0.1.1... Building text-1.2.2.1... Installed utf8-string-1.0.1.1 Configuring StateVar-1.1.0.4... Building StateVar-1.1.0.4... Configuring vector-0.11.0.0... Installed StateVar-1.1.0.4 Building vector-0.11.0.0... Installed text-1.2.2.1 Configuring hashable-1.2.5.0... Building hashable-1.2.5.0... Configuring OpenGLRaw-3.2.4.0... Installed hashable-1.2.5.0 Building OpenGLRaw-3.2.4.0... Installed vector-0.11.0.0 Configuring hashtables-1.2.1.0... Building hashtables-1.2.1.0... Installed hashtables-1.2.1.0 Configuring gtk2hs-buildtools-0.13.2.1... Building gtk2hs-buildtools-0.13.2.1... Installed gtk2hs-buildtools-0.13.2.1 Configuring cairo-0.13.3.1... Building cairo-0.13.3.1... Installed cairo-0.13.3.1 Installed OpenGLRaw-3.2.4.0 Configuring GLURaw-2.0.0.3... Building GLURaw-2.0.0.3... Installed GLURaw-2.0.0.3 Configuring OpenGL-3.0.1.0... Building OpenGL-3.0.1.0... Installed OpenGL-3.0.1.0 Configuring OpenAL-1.7.0.4... Configuring GLUT-2.7.0.10... Building OpenAL-1.7.0.4... Building GLUT-2.7.0.10... Installed OpenAL-1.7.0.4 Configuring ALUT-2.4.0.2... Building ALUT-2.4.0.2... Installed ALUT-2.4.0.2 Installed GLUT-2.7.0.10 Configuring topkata-0.0... Building topkata-0.0... Failed to install topkata-0.0 Build log ( /home/builder/.cabal/logs/topkata-0.0.log ): cabal: Entering directory '/tmp/cabal-tmp-4934/topkata-0.0' Configuring topkata-0.0... Building topkata-0.0... Preprocessing executable 'topkata' for topkata-0.0... [1 of 6] Compiling Vector ( Vector.hs, dist/build/topkata/topkata-tmp/Vector.o ) Vector.hs:34:16: error: • Could not deduce (Eq a) arising from the literal ‘0’ from the context: Num a bound by the instance declaration at Vector.hs:23:10-28 Possible fix: add (Eq a) to the context of the instance declaration • In the pattern: 0 In the pattern: V3 0 0 0 In an equation for ‘signum’: signum (V3 0 0 0) = 0 cabal: Leaving directory '/tmp/cabal-tmp-4934/topkata-0.0' cabal: Error: some packages failed to install: topkata-0.0 failed during the building phase. The exception was: ExitFailure 1