From 6263c7cea5e8340ab6d8d03397e87e920a6bfd72 Mon Sep 17 00:00:00 2001
From: Thomas Letan <lthms@soap.coffee>
Date: Tue, 18 Feb 2020 22:02:27 +0100
Subject: Do not extract Coq terms in Strongly-Specified Functions part 2

---
 site/posts/StronglySpecifiedFunctions.v        | 10 +++++-----
 site/posts/StronglySpecifiedFunctionsProgram.v | 20 +++-----------------
 2 files changed, 8 insertions(+), 22 deletions(-)

(limited to 'site/posts')

diff --git a/site/posts/StronglySpecifiedFunctions.v b/site/posts/StronglySpecifiedFunctions.v
index 3adfe50..55af679 100644
--- a/site/posts/StronglySpecifiedFunctions.v
+++ b/site/posts/StronglySpecifiedFunctions.v
@@ -1,9 +1,9 @@
-(** # <h1>Strongly-Specified Functions in Coq, part 1: using the <code>refine</code> Tactic</h1>#
+(** #<h1>Strongly-Specified Functions in Coq, part 1: using the <code>refine</code> Tactic</h1>#
 
-  This is the first article (initially published on #<span class="time">January
-  11, 2015</span>#) of a series of two on how to write strongly-specified
-  functions in Coq. You can read the next part #<a
-  href="/posts/StronglySpecifiedFunctionsProgram">here</a>#. *)
+    This is the first article (initially published on #<span
+    class="time">January 11, 2015</span>#) of a series of two on how to write
+    strongly-specified functions in Coq. You can read the next part #<a
+    href="/posts/StronglySpecifiedFunctionsProgram">here</a>#. *)
 
 (** I started to play with Coq, the interactive theorem prover
     developed by Inria, a few weeks ago. It is a very powerful tool,
diff --git a/site/posts/StronglySpecifiedFunctionsProgram.v b/site/posts/StronglySpecifiedFunctionsProgram.v
index 037b0dd..ae996e7 100644
--- a/site/posts/StronglySpecifiedFunctionsProgram.v
+++ b/site/posts/StronglySpecifiedFunctionsProgram.v
@@ -246,14 +246,8 @@ Defined.
     [{ v': vector A e | forall (i : nat | i < e), nth v' i = nth v i
     }]. However, this made the goals and hypotheses become very hard
     to read and to use. Sigma-types in sigma-types: not a good
-    idea. *)
+    idea.
 
-From Coq Require Import Extraction.
-
-Extraction Implicit take [a n].
-Extraction take.
-
-(**
 <<
 (** val take : 'a1 vector -> nat -> 'a1 vector **)
 
@@ -298,13 +292,9 @@ Next Obligation.
   now apply PeanoNat.Nat.nle_succ_0 in H.
 Defined.
 
-(*begin hide *)
-Extraction Implicit drop [a n].
-Extraction drop.
-(* end hide *)
 (** The proofs are easy to write, and the extracted code is exactly what one might
-    want it to be: *)
-(**
+    want it to be:
+
 <<
 (** val drop : 'a1 vector -> nat -> 'a1 vector **)
 let rec drop v = function
@@ -342,10 +332,6 @@ Next Obligation.
   lia.
 Defined.
 
-(*begin hide *)
-Extraction Implicit extract [a n].
-Extraction extract.
-(* end hide *)
 (** The proofs are straightforward because the specifications of [drop] and
     [take] are precise enough, and we do not need to have a look at their
     implementations. The extracted version of [extract] is as clean as we can
-- 
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