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+# What `#[derive(IsVariant)]` generates
+
+When an enum is decorated with `#[derive(IsVariant)]`, for each variant `foo` in
+the enum, a public instance method `is_foo(&self) -> bool` is generated. If you
+don't want the `is_foo` method generated for a variant you can put the
+`#[is_variant(ignore)]` attribute on that variant.
+
+
+
+
+## Example usage
+
+```rust
+# use derive_more::IsVariant;
+#
+#[derive(IsVariant)]
+enum Maybe<T> {
+    Just(T),
+    Nothing
+}
+
+assert!(Maybe::<()>::Nothing.is_nothing());
+assert!(!Maybe::<()>::Nothing.is_just());
+```
+
+
+### What is generated?
+
+The derive in the above example code generates the following code:
+```rust
+# enum Maybe<T> {
+#     Just(T),
+#     Nothing
+# }
+impl <T> Maybe<T>{
+    pub const fn is_just(&self) -> bool {
+        match self {Self::Just(..) => true, _ => false}
+    }
+    pub const fn is_nothing(&self) -> bool {
+        match self {Self::Nothing => true, _ => false}
+    }
+}
+```