added custom display example using flags_iter config option

examples/display.rs

@@ -0,0 +1,26 @@
+use bitmask_enum::bitmask;
+
+use std::fmt;
+
+#[bitmask(u8)]
+#[bitmask_config(flags_iter)]
+enum Bitmask {
+    Flag1, // defaults to 0d00000001
+    Flag2, // defaults to 0d00000010
+    Flag3, // defaults to 0d00000100
+}
+
+impl fmt::Display for Bitmask {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list()
+            .entries(Self::flags().filter_map(|&(name, value)| self.contains(value).then(|| name)))
+            .finish()
+    }
+}
+
+fn main() {
+    // Bitmask that contains Flag1 and Flag3
+    let bm = Bitmask::Flag1 | Bitmask::Flag3;
+
+    println!("{}", bm); // ["Flag1", "Flag3"]
+}