> i read a bit about fixed size arrays in it and the fact
> that 32 is the largest fixed size array
This is exceptionally mistaken, where did you read it? Arrays in Rust top out at the maximum value of a platform-sized pointer, which is either 2^32 or 2^64 depending on platform.
"Arrays of sizes from 0 to 32 (inclusive) implement the following traits if the element type allows it:
Clone (only if T: Copy)
Debug
IntoIterator (implemented for &[T; N] and &mut [T; N])
PartialEq, PartialOrd, Eq, Ord
Hash
AsRef, AsMut
Borrow, BorrowMut
Default
This limitation on the size N exists because Rust does not yet support code that is generic over the size of an array type. [Foo; 3] and [Bar; 3] are instances of same generic type [T; 3], but [Foo; 3] and [Foo; 5] are entirely different types. As a stopgap, trait implementations are statically generated up to size 32."
i sort of leapt to the conclusion that these traits couldn't be implemented because generically because the type system requires them to be implemented for each size of N, and they provide the first 32 as a nicety. the similarity to the situation with tuples in haskell, (http://stackoverflow.com/questions/2978389/haskell-tuple-siz...), and the fact that rust doesn't have dependent types and so a type couldn't depend on a value, and i just kind of guessed at a possible reason.
Ah I see, yes the explanation there is correct. The types exist up to ginormous sizes, but the standard library only implements certain convenience traits for certain sizes (though using newtypes, you can implement those traits yourself for any array size you want). The specific feature we're lacking is type-level numerals, which is on the way towards but not anywhere close to a dependent type system AIUI.
