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    // Super explicit first paragraph because this shows up at the top level and
    // trips up people who are just looking for basic Serialize / Deserialize
    // documentation.
    //
    /// Helper macro when implementing the `Deserializer` part of a new data format
    /// for Serde.
    ///
    /// Some [`Deserializer`] implementations for self-describing formats do not
    /// care what hint the [`Visitor`] gives them, they just want to blindly call
    /// the [`Visitor`] method corresponding to the data they can tell is in the
    /// input. This requires repetitive implementations of all the [`Deserializer`]
    /// trait methods.
    ///
    /// ```edition2018
    /// # use serde::forward_to_deserialize_any;
    /// # use serde::de::{value, Deserializer, Visitor};
    /// #
    /// # struct MyDeserializer;
    /// #
    /// # impl<'de> Deserializer<'de> for MyDeserializer {
    /// #     type Error = value::Error;
    /// #
    /// #     fn deserialize_any<V>(self, _: V) -> Result<V::Value, Self::Error>
    /// #     where
    /// #         V: Visitor<'de>,
    /// #     {
    /// #         unimplemented!()
    /// #     }
    /// #
    /// #[inline]
    /// fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    /// where
    ///     V: Visitor<'de>,
    /// {
    ///     self.deserialize_any(visitor)
    /// }
    /// #
    /// #     forward_to_deserialize_any! {
    /// #         i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
    /// #         bytes byte_buf option unit unit_struct newtype_struct seq tuple
    /// #         tuple_struct map struct enum identifier ignored_any
    /// #     }
    /// # }
    /// ```
    ///
    /// The `forward_to_deserialize_any!` macro implements these simple forwarding
    /// methods so that they forward directly to [`Deserializer::deserialize_any`].
    /// You can choose which methods to forward.
    ///
    /// ```edition2018
    /// # use serde::forward_to_deserialize_any;
    /// # use serde::de::{value, Deserializer, Visitor};
    /// #
    /// # struct MyDeserializer;
    /// #
    /// impl<'de> Deserializer<'de> for MyDeserializer {
    /// #   type Error = value::Error;
    /// #
    ///     fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    ///     where
    ///         V: Visitor<'de>,
    ///     {
    ///         /* ... */
    /// #       let _ = visitor;
    /// #       unimplemented!()
    ///     }
    ///
    ///     forward_to_deserialize_any! {
    ///         bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
    ///         bytes byte_buf option unit unit_struct newtype_struct seq tuple
    ///         tuple_struct map struct enum identifier ignored_any
    ///     }
    /// }
    /// ```
    ///
    /// The macro assumes the convention that your `Deserializer` lifetime parameter
    /// is called `'de` and that the `Visitor` type parameters on each method are
    /// called `V`. A different type parameter and a different lifetime can be
    /// specified explicitly if necessary.
    ///
    /// ```edition2018
    /// # use std::marker::PhantomData;
    /// #
    /// # use serde::forward_to_deserialize_any;
    /// # use serde::de::{value, Deserializer, Visitor};
    /// #
    /// # struct MyDeserializer<V>(PhantomData<V>);
    /// #
    /// # impl<'q, V> Deserializer<'q> for MyDeserializer<V> {
    /// #     type Error = value::Error;
    /// #
    /// #     fn deserialize_any<W>(self, visitor: W) -> Result<W::Value, Self::Error>
    /// #     where
    /// #         W: Visitor<'q>,
    /// #     {
    /// #         unimplemented!()
    /// #     }
    /// #
    /// forward_to_deserialize_any! {
    ///     <W: Visitor<'q>>
    ///     bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
    ///     bytes byte_buf option unit unit_struct newtype_struct seq tuple
    ///     tuple_struct map struct enum identifier ignored_any
    /// }
    /// # }
    /// ```
    ///
    /// [`Deserializer`]: trait.Deserializer.html
    /// [`Visitor`]: de/trait.Visitor.html
    /// [`Deserializer::deserialize_any`]: trait.Deserializer.html#tymethod.deserialize_any
    #[macro_export(local_inner_macros)]
    macro_rules! forward_to_deserialize_any {
        (<$visitor:ident: Visitor<$lifetime:tt>> $($func:ident)*) => {
            $(forward_to_deserialize_any_helper!{$func<$lifetime, $visitor>})*
        };
        // This case must be after the previous one.
        ($($func:ident)*) => {
            $(forward_to_deserialize_any_helper!{$func<'de, V>})*
        };
    }

    #[doc(hidden)]
    #[macro_export]
    macro_rules! forward_to_deserialize_any_method {
        ($func:ident<$l:tt, $v:ident>($($arg:ident : $ty:ty),*)) => {
            #[inline]
            fn $func<$v>(self, $($arg: $ty,)* visitor: $v) -> $crate::__private::Result<$v::Value, Self::Error>
            where
                $v: $crate::de::Visitor<$l>,
            {
                $(
                    let _ = $arg;
                )*
                self.deserialize_any(visitor)
            }
        };
    }

    #[doc(hidden)]
    #[macro_export(local_inner_macros)]
    macro_rules! forward_to_deserialize_any_helper {
        (bool<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_bool<$l, $v>()}
        };
        (i8<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_i8<$l, $v>()}
        };
        (i16<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_i16<$l, $v>()}
        };
        (i32<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_i32<$l, $v>()}
        };
        (i64<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_i64<$l, $v>()}
        };
        (i128<$l:tt, $v:ident>) => {
            serde_if_integer128! {
                forward_to_deserialize_any_method!{deserialize_i128<$l, $v>()}
            }
        };
        (u8<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_u8<$l, $v>()}
        };
        (u16<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_u16<$l, $v>()}
        };
        (u32<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_u32<$l, $v>()}
        };
        (u64<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_u64<$l, $v>()}
        };
        (u128<$l:tt, $v:ident>) => {
            serde_if_integer128! {
                forward_to_deserialize_any_method!{deserialize_u128<$l, $v>()}
            }
        };
        (f32<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_f32<$l, $v>()}
        };
        (f64<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_f64<$l, $v>()}
        };
        (char<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_char<$l, $v>()}
        };
        (str<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_str<$l, $v>()}
        };
        (string<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_string<$l, $v>()}
        };
        (bytes<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_bytes<$l, $v>()}
        };
        (byte_buf<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_byte_buf<$l, $v>()}
        };
        (option<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_option<$l, $v>()}
        };
        (unit<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_unit<$l, $v>()}
        };
        (unit_struct<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_unit_struct<$l, $v>(name: &'static str)}
        };
        (newtype_struct<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_newtype_struct<$l, $v>(name: &'static str)}
        };
        (seq<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_seq<$l, $v>()}
        };
        (tuple<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_tuple<$l, $v>(len: usize)}
        };
        (tuple_struct<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_tuple_struct<$l, $v>(name: &'static str, len: usize)}
        };
        (map<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_map<$l, $v>()}
        };
        (struct<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_struct<$l, $v>(name: &'static str, fields: &'static [&'static str])}
        };
        (enum<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_enum<$l, $v>(name: &'static str, variants: &'static [&'static str])}
        };
        (identifier<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_identifier<$l, $v>()}
        };
        (ignored_any<$l:tt, $v:ident>) => {
            forward_to_deserialize_any_method!{deserialize_ignored_any<$l, $v>()}
        };
    }