On 18 May 2011 13:44,
for example:
I will ask the glorious compiler, and it says:
*Main> :t calcFFT calcFFT :: (Math.FFT.Base.FFTWReal r) => V.Vector (Complex r) -> V.Vector (Complex r)
I then put the signature in my code, reload it, and:
Not in scope: type constructor or class `Math.FFT.Base.FFTWReal'
It seems very strange to me that the fully qualified module name doesn't work, nor does any combination thereof, e.g. FFT.FFTWReal, FFT.Base.FFTWReal, etc...
I'm importing FFT as:
import qualified Math.FFT as FFT
What's happening is that the type involves the FFTWReal class. However, this isn't immediately visible to ghci as it isn't in scope, but it can figure out that it's found in Math.FFT.Base. As such, you need to import that module as well (as opposed to just the Math.FFT class you have already imported). -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com