diff --git a/src/dreammaker/ast.rs b/src/dreammaker/ast.rs
index 18299629..a8070038 100644
--- a/src/dreammaker/ast.rs
+++ b/src/dreammaker/ast.rs
@@ -336,7 +336,7 @@ pub enum Expression {
         /// The unary operations applied to this value, in reverse order.
         unary: Vec<UnaryOp>,
         /// The term of the expression.
-        term: Spanned<Term>,
+        term: Box<Spanned<Term>>,
         /// The follow operations applied to this value.
         follow: Vec<Spanned<Follow>>,
     },
@@ -486,7 +486,7 @@ impl From<Term> for Expression {
             term => Expression::Base {
                 unary: vec![],
                 follow: vec![],
-                term: Spanned::new(Default::default(), term),
+                term: Box::new(Spanned::new(Default::default(), term)),
             },
         }
     }
diff --git a/src/dreammaker/constants.rs b/src/dreammaker/constants.rs
index 585929a7..b013f02e 100644
--- a/src/dreammaker/constants.rs
+++ b/src/dreammaker/constants.rs
@@ -760,12 +760,8 @@ impl<'a> ConstantFolder<'a> {
                     if args.len() != 1 {
                         return Err(self.error(format!("malformed defined() call, must have 1 argument and instead has {}", args.len())));
                     }
-                    match args[0] {
-                        Expression::Base {
-                            ref unary,
-                            term: Spanned { elem: Term::Ident(ref ident), .. },
-                            ref follow
-                        } if unary.is_empty() && follow.is_empty() => {
+                    match args[0].as_term() {
+                        Some(Term::Ident(ref ident)) => {
                             Constant::Int(if defines.contains_key(ident) { 1 } else { 0 })
                         },
                         _ => return Err(self.error("malformed defined() call, argument given isn't an Ident.")),
diff --git a/src/dreammaker/parser.rs b/src/dreammaker/parser.rs
index de9d765b..cc2de1a4 100644
--- a/src/dreammaker/parser.rs
+++ b/src/dreammaker/parser.rs
@@ -1879,7 +1879,7 @@ impl<'ctx, 'an, 'inp> Parser<'ctx, 'an, 'inp> {
 
         success(Expression::Base {
             unary: unary_ops,
-            term,
+            term: Box::new(term),
             follow,
         })
     }