From 827969ae84ea5d10d0e1c20266e3837c9f907765 Mon Sep 17 00:00:00 2001
From: Marek Kaluba <kalmar@amu.edu.pl>
Date: Thu, 13 Oct 2022 23:41:05 +0200
Subject: [PATCH] use KB.IndexAutomaton as rewriting for FPGroups

---
 src/aut_groups/mcg.jl    | 12 +++++++-----
 src/aut_groups/sautFn.jl |  4 +++-
 src/types.jl             |  2 +-
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/aut_groups/mcg.jl b/src/aut_groups/mcg.jl
index 0bb17b2..fff9510 100644
--- a/src/aut_groups/mcg.jl
+++ b/src/aut_groups/mcg.jl
@@ -51,12 +51,14 @@ function SurfaceGroup(genus::Integer, boundaries::Integer)
         comms = Word(word)
         word_rels = [ comms => one(comms) ]
 
-        rws = KnuthBendix.RewritingSystem(word_rels, KnuthBendix.RecursivePathOrder(Al))
-        KnuthBendix.knuthbendix!(rws)
+        rws = let R = KnuthBendix.RewritingSystem(word_rels, KnuthBendix.Recursive(Al))
+            KnuthBendix.IndexAutomaton(KnuthBendix.knuthbendix(R))
+        end
     elseif boundaries == 1
-        S = typeof(one(Word(Int[])))
-        word_rels = Pair{S, S}[]
-        rws = RewritingSystem(word_rels, KnuthBendix.LenLex(Al))
+        word_rels = Pair{W,W}[]
+        rws = let R = RewritingSystem(word_rels, KnuthBendix.LenLex(Al))
+            KnuthBendix.IndexAutomaton(KnuthBendix.knuthbendix(R))
+        end
     else
         throw("Not Implemented")
     end
diff --git a/src/aut_groups/sautFn.jl b/src/aut_groups/sautFn.jl
index 4f8c609..fdc37cf 100644
--- a/src/aut_groups/sautFn.jl
+++ b/src/aut_groups/sautFn.jl
@@ -14,7 +14,9 @@ function SpecialAutomorphismGroup(F::FreeGroup; ordering = KnuthBendix.LenLex, k
         # the rws is not confluent, let's suppress warning about it
         KnuthBendix.knuthbendix(rws, KnuthBendix.Settings(; max_rules=max_rules, kwargs...))
     end
-    return AutomorphismGroup(F, S, rws, ntuple(i -> gens(F, i), n))
+
+    idxA = KnuthBendix.IndexAutomaton(rws)
+    return AutomorphismGroup(F, S, idxA, ntuple(i -> gens(F, i), n))
 end
 
 KnuthBendix.alphabet(G::AutomorphismGroup{<:FreeGroup}) = alphabet(rewriting(G))
diff --git a/src/types.jl b/src/types.jl
index cb50fe0..5ccd283 100644
--- a/src/types.jl
+++ b/src/types.jl
@@ -231,7 +231,7 @@ function FPGroup(
 
     rws = KnuthBendix.knuthbendix(rws, KnuthBendix.Settings(; kwargs...))
 
-    return FPGroup(G.gens, rels, rws)
+    return FPGroup(G.gens, rels, KnuthBendix.IndexAutomaton(rws))
 end
 
 function Base.show(io::IO, ::MIME"text/plain", G::FPGroup)