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Array Array definition problem
f#

I'm having a little problem with a ref array array definition:

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let walls = ref [||];;
let get_wall i j = !walls.(i).(j);;

-><i> this expression has type 'a array ref but is here used with type 'a ref array array.<i> I don't get any problems on Ocaml using that sintax. Any ideas wath am i doing wrong?

.

One way to solve that is to add a dummy arg and use parentheses. It seems that the precedence of the ! operator is different in ocaml.

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let walls () = ref [||]
let get_wall i j = (!walls()).(i).(j);;
By on 2/26/2008 10:19 AM ()

This can be further simplified by removing the dummy variable. So, it would simply become:

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let walls = ref [||];;
let get_wall i j = (!walls).(i).(j)

The dummy variable is only necessary for preventing errors if typing each line separately into the interpreter (FSI). If using an editor like VS 2005/2008, it is not required as the type checker will be able to use successive functions/usage for type inference.

Regards,

z.

By on 2/26/2008 11:24 AM ()

I still get an error using your way zakaluka. A value restriction.
--edit--
Im a bad reader... you used floating constraints later...ok

:$

By on 2/26/2008 11:56 AM ()

Problem solved.

Thank you both. :)

By on 2/26/2008 11:44 AM ()

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