1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236

// 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>()}
    };
}