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Re: [Coq-Club] Sigma Type Coercion

From: Luke Palmer <lrpalmer AT gmail.com>
To: Julio <coquser AT googlemail.com>
Cc: coq-club AT pauillac.inria.fr
Subject: Re: [Coq-Club] Sigma Type Coercion
Date: Wed, 9 Sep 2009 06:32:06 -0600
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On Wed, Sep 9, 2009 at 5:01 AM, Julio
<coquser AT googlemail.com>
wrote:
> Is sigma type coercion possible?
>
> Require Import String.
> Open Scope string_scope.
> Record A:Set := {total:nat}.
> Record B:Set := {name:string}.
>
> (*Sigma types.*)
> Definition ASig := {a:A | (total a) > 10}.
> Definition BSig := {b:B | (name b) = "kilometers"}.
> (*Syntax for Coercion ASig >-> BSig ?*)

The same as all other coercions.

Definition ASig_to_BSig : ASig -> BSig := ...
Coercion ASig_to_BSig : ASig >-> BSig.

Luke

[Coq-Club] Sigma Type Coercion, Julio
- Re: [Coq-Club] Sigma Type Coercion, Luke Palmer
  - Re: [Coq-Club] Sigma Type Coercion, Julio
    - Re: [Coq-Club] Sigma Type Coercion, Adam Chlipala
      - Re: [Coq-Club] Sigma Type Coercion, Adam Chlipala