before a major refactor

I decide to adopt a new approach of recording and updating item
derivation forests.  Since this affects a lot of things, I decide to
commit before the refactor, so that I can create a branch for that
refactor.

1 files changed, 2 insertions, 1 deletions

diff --git a/nfa/src/default/regex.rs b/nfa/src/default/regex.rs
index 5e0d53b..1c22687 100644
--- a/nfa/src/default/regex.rs
+++ b/nfa/src/default/regex.rs
@@ -4,6 +4,7 @@ use graph::{error::Error as GError, ALGraph, ExtGraph, Graph, GraphLabel};
 
 use crate::{desrec::DesRec, error::Error, Regex};
 
+#[cfg(feature = "recursion")]
 use receme::{algebra::Algebra, catana::Cata};
 
 use std::{
@@ -193,7 +194,7 @@ impl<T: GraphLabel> DefaultRegex<T> {
     }
 }
 
-// REVIEW: This may not be needed.
+#[cfg(feature = "recursion")]
 impl<S: GraphLabel, T, A> Cata<T, Vec<T>, A> for &DefaultRegex<S>
 where
     A: Algebra<T, Vec<T>>,