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[Caml-list] Should be INSIDE STANDARD-LIB: Hashtbl.keys

oliver@f...
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    - Xavier Leroy
      - Jon Harrop
        
        Jon Harrop
        
        John Goerzen
        
        Florian Hars
      - John Goerzen
        
        John Goerzen
  - Richard Jones
    - skaller
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        skaller
      - Jean-Christophe Filliatre
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        oliver@f...
- John Goerzen

Date:	-- (:)
From:	Jean-Christophe Filliatre <Jean-Christophe.Filliatre@l...>
Subject:	Re: [Caml-list] Should be INSIDE STANDARD-LIB: Hashtbl.keys

skaller writes:
 > 
 > The problem is that the Ocaml hashtbl isn't a conventional
 > hash table. It allows multiple bindings which means it
 > cannot be treated as a simple container.

It's  probably done  on  purpose.  Indeed, it  is  very convenient  to
implement symbol tables --- in an imperative way --- because with this
semantics for Hashtbl.add a new  binding really hides any previous one
until the end of its  scope where Hashtbl.remove restores the previous
binding.

This has nothing to do with Ocaml; I'm pretty sure you can find C hash
tables implementations with the same feature.

-- 
Jean-Christophe

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