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Subject: RE: [Caml-list] Accessing constructors (tags) from C
From: Mathias Kende <mathias@kende.fr>
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Date: Sun, 23 Nov 2008 22:49:20 +0100
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Le dimanche 23 novembre 2008 =C3=A0 18:42 +0000, David Allsopp a =C3=A9crit=
 :
> See Section 18.3.4 of the manual. In your example below, Null is an
> integer
> 0 and Int is a 1-word block with tag 1. In C, Null is Val_int(0) and t
> =3D
> Int(x) is caml_alloc(1, 1); Store_field(t, 0, Val_int(x)).

(Int x) is t =3D caml_alloc(1,0); Store_field(t,0,Val_int(x)). Because the
numbering of the fields starts from zero separately for the constant and
non-constant constructors (definitely, this is error prone).

Mathias