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From: Jacques Garrigue <garrigue@math.nagoya-u.ac.jp>
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Date: Mon, 2 May 2011 22:33:54 +0900
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Subject: Re: [Caml-list] Pattern-matching on Ocaml records

On 2011/05/02, at 22:16, Create Software wrote:

>> Only the record field itself is mutable. Extracting only gives you a value, not a reference.
> 
> Sure, but how come that
>    let reset {label = lbl} = lbl <- 0;;
> works fine in Caml Light and not in OCaml?

This has been deprecated.
Namely, this introduced a notion of lvalue, only for mutable record labels (and actually also for sum types IIRC).
The current approach of always requiring to specify the record is clearer, and it extends naturally the notations
   a.(i) <- e  for arrays
   s.[i] <- e  for strings

This said, later on object instance variables were added as lvalues, so the uniformity argument is not so strong...

Jacques Garrigue