[Haskell-cafe] Basic question concerning data constructors

Luke Palmer lrpalmer at gmail.com
Tue Jan 1 18:57:20 EST 2008


On Jan 1, 2008 3:43 PM, Yitzchak Gale <gale at sefer.org> wrote:
> The classical definition of "general recursive function"
> refers to functions in Integer -> Integer to begin
> with, so there can only be countably many values by
> construction.

Except that there are uncountably many (2^Aleph_0) functions in
Integer -> Integer.  That doesn't change the fact that there are
countably many computable functions, as you guys have been saying.
But I think you need to refer to the LC or Turing machine definition
to get countability.

Luke


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