fix(backends/lean): `as` is a keyword

`as` is a reserved keyword and cannot be used as a variable name.

Fixes #139.

Signed-off-by: Ryan Lahfa <ryan.lahfa@inria.fr>

1 files changed, 1 insertions, 0 deletions

diff --git a/compiler/ExtractBase.ml b/compiler/ExtractBase.ml
index 656d2f27..718325d2 100644
--- a/compiler/ExtractBase.ml
+++ b/compiler/ExtractBase.ml
@@ -915,6 +915,7 @@ let keywords () =
         ]
     | Lean ->
         [
+          "as";
           "by";
           "class";
           "decreasing_by";