Resolving dependencies...
Downloading numeric-quest-0.1.1.3...
Configuring numeric-quest-0.1.1.3...
Building numeric-quest-0.1.1.3...
Preprocessing library numeric-quest-0.1.1.3...
[1 of 8] Compiling Tensor           ( Tensor.lhs, dist/build/Tensor.o )

Tensor.lhs:556:3: Warning:
    Pattern match(es) are non-exhaustive
    In an equation for `contract': Patterns not matched: _ _ _
[2 of 8] Compiling Roots            ( Roots.hs, dist/build/Roots.o )

Roots.hs:85:12:
    Could not deduce (Eq a) arising from a use of `=='
    from the context (Num a)
      bound by the type signature for
                 polynomial_derivative :: Num a => [a] -> [a]
      at Roots.hs:79:26-44
    Possible fix:
      add (Eq a) to the context of
        the type signature for polynomial_derivative :: Num a => [a] -> [a]
    In the expression: as == []
    In a stmt of a pattern guard for
                   an equation for `polynomial_derivative':
      as == []
    In an equation for `polynomial_derivative':
        polynomial_derivative as
          | as == [] = []
          | otherwise = deriv 1 (drop 1 as) []
          where
              deriv n bs cs
                | bs == [] = reverse2 cs
                | otherwise = deriv (n + 1) (tail bs) ((n * (head bs)) : cs)
              reverse2 cs
                | cs == [] = []
                | otherwise = reverse cs
Failed to install numeric-quest-0.1.1.3
cabal: Error: some packages failed to install:
numeric-quest-0.1.1.3 failed during the building phase. The exception was:
ExitFailure 1