Re: [Haskell-cafe] Referential Transparency and Monads

[Brandon S. Allbery KF8NH]

On 2009 Apr 10, at 1:00, Jonathan Cast wrote:

On Fri, 2009-04-10 at 07:29 +0400, Miguel Mitrofanov wrote:

On 10 Apr 2009, at 06:30, Jonathan Cast wrote:

do
   s <- readFile "/my_file"
   writeFile "/my_file" "Hello, world!\n"
   threadDelay 10000 -- If you don't like threadDelay, just
substitute forcing
                     -- an expensive thunk here
   writeFile "/my_file" s


the identity;

As a function from initial state to final state, this program is just

No, since world state includes the user state itself, not just files
contents.

My programs are passing me around inside a state token?

--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allb...@kf8nh.com
system administrator [openafs,heimdal,too many hats] allb...@ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH

You seem to have redefined "conceptually" to mean "in absolute literalness".

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