Updated api bootstrap

crates/mist-api/src/modules.mist

@@ -16,7 +16,7 @@ pub class Module {
     pub constructor(PathBuf mist_path, MistConfig& config) {
         self.children = Vec::new();
         self.name = mist_path.file_stem()
-            .and_then(fn(s) -> s.to_str())
+            .and_then((s) => s.to_str())
             .expect("Failed to get module name")
             .to_string();
         self.path = mist_path;
@@ -66,7 +66,7 @@ pub class Module {
     }
 
     pub bool is_package(&self) {
-        self.path.file_name().map(fn(v) -> v.to_str()).unwrap_or_default() == Some("package.mist")
+        self.path.file_name().map((v) => v.to_str()).unwrap_or_default() == Some("package.mist")
     }
 
     pub PathBuf output_dir(&self, PathBuf& parent_dir) {