diff --git a/src/atrule/function.rs b/src/atrule/function.rs
index 21543ba..f0a5ee5 100644
--- a/src/atrule/function.rs
+++ b/src/atrule/function.rs
@@ -68,26 +68,28 @@ impl Function {
         scope: &Scope,
         super_selector: &Selector,
     ) -> SassResult<()> {
+        let mut scope = scope.clone();
         for (idx, arg) in self.args.0.iter().enumerate() {
             if arg.is_variadic {
                 let span = args.span();
-                self.scope.insert_var(
+                let arg_list = Value::ArgList(args.get_variadic(&mut scope, super_selector)?);
+                scope.insert_var(
                     &arg.name,
                     Spanned {
-                        node: Value::ArgList(args.get_variadic(scope, super_selector)?),
+                        node: arg_list,
                         span,
                     },
                 )?;
                 break;
             }
-            let val = match args.get_positional(idx, scope, super_selector) {
+            let val = match args.get_positional(idx, &mut scope, super_selector) {
                 Some(v) => v?,
-                None => match args.get_named(arg.name.clone(), scope, super_selector) {
+                None => match args.get_named(arg.name.clone(), &mut scope, super_selector) {
                     Some(v) => v?,
                     None => match &arg.default {
                         Some(v) => Value::from_tokens(
                             &mut v.iter().cloned().peekmore(),
-                            scope,
+                            &mut scope,
                             super_selector,
                         )?,
                         None => {
@@ -98,8 +100,9 @@ impl Function {
                     },
                 },
             };
-            self.scope.insert_var(&arg.name, val)?;
+            scope.insert_var(&arg.name, val)?;
         }
+        self.scope.extend(scope);
         Ok(())
     }
 
diff --git a/src/lib.rs b/src/lib.rs
index 291e86c..344d00a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -261,7 +261,7 @@ impl StyleSheet {
     /// ```
     #[inline]
     #[cfg(not(feature = "wasm"))]
-    pub fn from_path<P: AsRef<Path> + Into<String> + Clone>(p: &P) -> SassResult<String> {
+    pub fn from_path(p: &str) -> SassResult<String> {
         let mut map = CodeMap::new();
         let file = map.add_file(p.clone().into(), String::from_utf8(fs::read(p.clone())?)?);
         Css::from_stylesheet(StyleSheet(
diff --git a/tests/args.rs b/tests/args.rs
index 9527242..d72e02e 100644
--- a/tests/args.rs
+++ b/tests/args.rs
@@ -40,3 +40,8 @@ test!(
     "@function foo($arg1: bar()) {\n    @return true;\n}\n\na {\n    color: foo();\n}\n",
     "a {\n  color: true;\n}\n"
 );
+test!(
+    self_referential_default_arg_value,
+    "@function foo($a, $b: $a) {\n    @return $b;\n}\n\na {\n    color: foo(2);\n}\n",
+    "a {\n  color: 2;\n}\n"
+);