Arrays and boxed/unboxed data

Arrays and boxed/unboxed data

[Erik de Castro Lopo]

Hi all,

I'm about to start some work on an algorithm which will need a 
quite large 2-D array of Ocaml ints.

I assume that Arrays of ints will be unboxed. Is that correct?

What about other types? For instance:

    type my_enum = A | B | C

If I made an array of my_enum would that be unboxed?

Is there any general rule that will tell me what is boxed and
what is unboxed? If I define an Array of some data type is
there a way of figuring this out?

TIA,
Erik
-- 
+-----------------------------------------------------------+
  Erik de Castro Lopo
+-----------------------------------------------------------+
"I want to make sure (a user) can't get through ... an online
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Re: [Caml-list] Arrays and boxed/unboxed data

[Eric Cooper]

On Thu, Jul 06, 2006 at 10:27:21AM +1000, Erik de Castro Lopo wrote:
> Is there any general rule that will tell me what is boxed and
> what is unboxed?

Section 18.3 of the manual.

-- 
Eric Cooper             e c c @ c m u . e d u

Re: [Caml-list] Arrays and boxed/unboxed data

[Tom]

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However, assuming you need a 2 dimensional array, that is int array array,
the second array will be boxed (elements of the first array will be pointers
to another array, but elements of these, secondary, arrays will be unboxed
integers).

You could probably use one dimensional array and use a modified getter and
setter functions that would transform 2-D indeces into 1-D indeeces. In this
way, all the elements would be unboxed.

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Re: [Caml-list] Arrays and boxed/unboxed data

[Jon Harrop]

On Saturday 08 July 2006 16:25, Tom wrote:
> You could probably use one dimensional array and use a modified getter and
> setter functions that would transform 2-D indeces into 1-D indeeces. In
> this way, all the elements would be unboxed.

Although you're likely to hit the max array length limit on 32-bit.

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
Objective CAML for Scientists
http://www.ffconsultancy.com/products/ocaml_for_scientists