diff --git a/compiler/fluxc_parser/src/lib.rs b/compiler/fluxc_parser/src/lib.rs
index 49f999e..3e11137 100644
--- a/compiler/fluxc_parser/src/lib.rs
+++ b/compiler/fluxc_parser/src/lib.rs
@@ -1,6 +1,4 @@
 //! Defines the parser for Flux code.
-#![feature(option_result_contains)]
-
 use std::rc::Rc;
 
 use fluxc_ast::{Ident, Node, Stmt, AST};
@@ -12,6 +10,7 @@ mod expr;
 mod span;
 mod stmt;
 mod ty;
+mod util;
 
 /// Internal moduel to prevent leakage of the `Rule` type to external
 /// crates.
diff --git a/compiler/fluxc_parser/src/stmt/func_decl.rs b/compiler/fluxc_parser/src/stmt/func_decl.rs
index 73e3704..81d7231 100644
--- a/compiler/fluxc_parser/src/stmt/func_decl.rs
+++ b/compiler/fluxc_parser/src/stmt/func_decl.rs
@@ -3,7 +3,7 @@ use fluxc_span::Span;
 use fluxc_types::Type;
 use pest::iterators::Pair;
 
-use crate::{unexpected_rule, Context, PResult, Parse, Rule};
+use crate::{unexpected_rule, Context, PResult, Parse, Rule, util::Contains};
 
 impl Parse for FuncCall {
     #[tracing::instrument]
diff --git a/compiler/fluxc_parser/src/util.rs b/compiler/fluxc_parser/src/util.rs
new file mode 100644
index 0000000..931bbe2
--- /dev/null
+++ b/compiler/fluxc_parser/src/util.rs
@@ -0,0 +1,13 @@
+pub trait Contains<P: PartialEq> {
+	/// Test if the target contains `other`.
+	fn contains(&self, other: &P) -> bool;
+}
+
+impl <P: PartialEq> Contains<P> for Option<P> {
+    fn contains(&self, other: &P) -> bool {
+        match self.as_ref() {
+            Some(s) => s.eq(other),
+            None => false,
+        }
+    }
+}