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From: Thierry Martinez <thierry.martinez@inria.fr>
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Subject: Re: [Caml-list] Bless me Father, for I have used Obj.magic

rixed@happyleptic.org :
> let make ... =
> 	let some_operation t_priv t1 =
> 		... use t_priv to return a t2 ... in
> 	let rec t_priv = { t ;
> 	                   some_other_fields = some_values }
> 	and t = { operation = some_operation t_priv ;
> 	          some_fields = some_values }
> 	in t
>
> This does not compile because of the way t_priv is used within t
> construction. The policed way to get around this seams to be:

This will compile if you η-expand the partial application of
some_operation into “(fun t1 -> some_operation t_priv t1)”.

But perhaps your example is over simplified and hide the real
difficulty.

-- 
Thierry.