**diff options**

-rw-r--r-- | site/posts/StronglySpecifiedFunctions.v | 10 | ||||

-rw-r--r-- | site/posts/StronglySpecifiedFunctionsProgram.v | 20 |

2 files changed, 8 insertions, 22 deletions

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 |