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Diffstat (limited to 'theories/Logic/Description.v')
| -rw-r--r-- | theories/Logic/Description.v | 21 |
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diff --git a/theories/Logic/Description.v b/theories/Logic/Description.v new file mode 100644 index 00000000..962f2a2a --- /dev/null +++ b/theories/Logic/Description.v @@ -0,0 +1,21 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(************************************************************************) + +(*i $Id: Description.v 10170 2007-10-03 14:41:25Z herbelin $ i*) + +(** This file provides a constructive form of definite description; it + allows to build functions from the proof of their existence in any + context; this is weaker than Church's iota operator *) + +Require Import ChoiceFacts. + +Set Implicit Arguments. + +Axiom constructive_definite_description : + forall (A : Type) (P : A->Prop), + (exists! x, P x) -> { x : A | P x }. |