repl output drops uninformative self bindings

1 files changed, 9 insertions, 1 deletions

diff --git a/bin/main.ml b/bin/main.ml
index 26375da..ede8ac5 100644
--- a/bin/main.ml
+++ b/bin/main.ml
@@ -9,11 +9,19 @@ let print_solutions solutions =
   | solutions ->
       List.iter
         (fun { Sol.Vm.bindings; residue } ->
+          (* A variable resolved to itself carries no information;
+             its constraints, if any, are in the residue. *)
+          let informative =
+            List.filter
+              (fun (variable, pattern) ->
+                not (Sol.Pattern.equal pattern (Sol.Pattern.Var variable)))
+              bindings
+          in
           let parts =
             List.map
               (fun (variable, pattern) ->
                 Format.asprintf "%s = %a" variable Sol.Pattern.pp pattern)
-              bindings
+              informative
             @ List.map (Format.asprintf "%a" Sol.Vm.pp_residual) residue
           in
           match parts with