On Mar 7, 2010, at 12:56 PM, Don Stewart wrote:
In fact, infinite vectors make no sense, as far as I can tell -- these are fundamentally bounded structures.
Fourier analysis? Functional analysis? Hamel bases in Real analysis? There are lots of infinite dimensional vector spaces out there.
GHC even optimizes it to:
fib = fib
Sounds like an implementation bug, not an infinite dimensional vector space bug. My guess is that strictness is getting in the way, and forcing what would be a lazy call to fib in the corresponding list code -- fib = 0 : 1 : (zipWith (+) fib (tail fib)) -- into a strict one. In fact, I'm pretty sure that's what the problem is: data Vector a = Vector {-# UNPACK #-} !Int {-# UNPACK #-} !Int {-# UNPACK #-} !(Array a) The !'s mean "strict" right?