diff --git a/hugr-core/src/std_extensions/collections/array.rs b/hugr-core/src/std_extensions/collections/array.rs
index 8fc1fe6fe..c1ccfe57e 100644
--- a/hugr-core/src/std_extensions/collections/array.rs
+++ b/hugr-core/src/std_extensions/collections/array.rs
@@ -36,40 +36,49 @@ pub const VERSION: semver::Version = semver::Version::new(0, 1, 0);
 
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 /// Statically sized array of values, all of the same type.
-pub struct ArrayValue(Vec<Value>, Type);
+pub struct ArrayValue {
+    values: Vec<Value>,
+    typ: Type,
+}
 
 impl ArrayValue {
     /// Create a new [CustomConst] for an array of values of type `typ`.
     /// That all values are of type `typ` is not checked here.
     pub fn new(typ: Type, contents: impl IntoIterator<Item = Value>) -> Self {
-        Self(contents.into_iter().collect_vec(), typ)
+        Self {
+            values: contents.into_iter().collect_vec(),
+            typ,
+        }
     }
 
     /// Create a new [CustomConst] for an empty array of values of type `typ`.
     pub fn new_empty(typ: Type) -> Self {
-        Self(vec![], typ)
+        Self {
+            values: vec![],
+            typ,
+        }
     }
 
     /// Returns the type of the `[ArrayValue]` as a `[CustomType]`.`
     pub fn custom_type(&self) -> CustomType {
-        array_custom_type(self.0.len() as u64, self.1.clone())
+        array_custom_type(self.values.len() as u64, self.typ.clone())
     }
 
     /// Returns the type of values inside the `[ArrayValue]`.
     pub fn get_element_type(&self) -> &Type {
-        &self.1
+        &self.typ
     }
 
     /// Returns the values contained inside the `[ArrayValue]`.
     pub fn get_contents(&self) -> &[Value] {
-        &self.0
+        &self.values
     }
 }
 
 impl TryHash for ArrayValue {
     fn try_hash(&self, mut st: &mut dyn Hasher) -> bool {
-        maybe_hash_values(&self.0, &mut st) && {
-            self.1.hash(&mut st);
+        maybe_hash_values(&self.values, &mut st) && {
+            self.typ.hash(&mut st);
             true
         }
     }
@@ -100,7 +109,11 @@ impl CustomConst for ArrayValue {
 
         // constant can only hold classic type.
         let ty = match typ.args() {
-            [TypeArg::BoundedNat { n }, TypeArg::Type { ty }] if *n as usize == self.0.len() => ty,
+            [TypeArg::BoundedNat { n }, TypeArg::Type { ty }]
+                if *n as usize == self.values.len() =>
+            {
+                ty
+            }
             _ => {
                 return Err(CustomCheckFailure::Message(format!(
                     "Invalid array type arguments: {:?}",
@@ -110,7 +123,7 @@ impl CustomConst for ArrayValue {
         };
 
         // check all values are instances of the element type
-        for v in &self.0 {
+        for v in &self.values {
             if v.get_type() != *ty {
                 return Err(CustomCheckFailure::Message(format!(
                     "Array element {v:?} is not of expected type {ty}"
@@ -126,7 +139,7 @@ impl CustomConst for ArrayValue {
     }
 
     fn extension_reqs(&self) -> ExtensionSet {
-        ExtensionSet::union_over(self.0.iter().map(Value::extension_reqs))
+        ExtensionSet::union_over(self.values.iter().map(Value::extension_reqs))
             .union(EXTENSION_ID.into())
     }
 
@@ -134,10 +147,10 @@ impl CustomConst for ArrayValue {
         &mut self,
         extensions: &WeakExtensionRegistry,
     ) -> Result<(), ExtensionResolutionError> {
-        for val in &mut self.0 {
+        for val in &mut self.values {
             resolve_value_extensions(val, extensions)?;
         }
-        resolve_type_extensions(&mut self.1, extensions)
+        resolve_type_extensions(&mut self.typ, extensions)
     }
 }
 
@@ -239,11 +252,17 @@ mod test {
 
     #[test]
     fn test_array_value() {
-        let array_value = ArrayValue(vec![ConstUsize::new(3).into()], usize_t());
+        let array_value = ArrayValue {
+            values: vec![ConstUsize::new(3).into()],
+            typ: usize_t(),
+        };
 
         array_value.validate().unwrap();
 
-        let wrong_array_value = ArrayValue(vec![ConstF64::new(1.2).into()], usize_t());
+        let wrong_array_value = ArrayValue {
+            values: vec![ConstF64::new(1.2).into()],
+            typ: usize_t(),
+        };
         assert!(wrong_array_value.validate().is_err());
     }
 }