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</pre><pre class='rust '>
<span class='attribute'>#[<span class='ident'>cfg</span>(<span class='ident'>feature</span> <span class='op'>=</span> <span class='string'>"std"</span>)]</span>
<span class='attribute'>#[<span class='ident'>doc</span>(<span class='ident'>hidden</span>)]</span>
<span class='attribute'>#[<span class='ident'>macro_export</span>]</span>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>forward_to_deserialize_method</span> {
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span>:<span class='ident'>ident</span>($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>arg</span>:<span class='ident'>ty</span>),<span class='kw-2'>*</span>)) <span class='op'>=></span> {
<span class='attribute'>#[<span class='ident'>inline</span>]</span>
<span class='kw'>fn</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span><span class='op'><</span><span class='ident'>__V</span><span class='op'>></span>(<span class='self'>self</span>, $(_: <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>arg</span>,)<span class='op'>*</span> <span class='ident'>visitor</span>: <span class='ident'>__V</span>) <span class='op'>-></span> ::<span class='ident'>std</span>::<span class='ident'>result</span>::<span class='prelude-ty'>Result</span><span class='op'><</span><span class='ident'>__V</span>::<span class='ident'>Value</span>, <span class='self'>Self</span>::<span class='ident'>Error</span><span class='op'>></span>
<span class='kw'>where</span> <span class='ident'>__V</span>: <span class='macro-nonterminal'>$</span><span class='kw'>crate</span>::<span class='macro-nonterminal'>de</span>::<span class='ident'>Visitor</span>
{
<span class='self'>self</span>.<span class='ident'>deserialize</span>(<span class='ident'>visitor</span>)
}
};
}
<span class='attribute'>#[<span class='ident'>cfg</span>(<span class='ident'>not</span>(<span class='ident'>feature</span> <span class='op'>=</span> <span class='string'>"std"</span>))]</span>
<span class='attribute'>#[<span class='ident'>doc</span>(<span class='ident'>hidden</span>)]</span>
<span class='attribute'>#[<span class='ident'>macro_export</span>]</span>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>forward_to_deserialize_method</span> {
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span>:<span class='ident'>ident</span>($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>arg</span>:<span class='ident'>ty</span>),<span class='kw-2'>*</span>)) <span class='op'>=></span> {
<span class='attribute'>#[<span class='ident'>inline</span>]</span>
<span class='kw'>fn</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span><span class='op'><</span><span class='ident'>__V</span><span class='op'>></span>(<span class='self'>self</span>, $(_: <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>arg</span>,)<span class='op'>*</span> <span class='ident'>visitor</span>: <span class='ident'>__V</span>) <span class='op'>-></span> ::<span class='ident'>core</span>::<span class='ident'>result</span>::<span class='prelude-ty'>Result</span><span class='op'><</span><span class='ident'>__V</span>::<span class='ident'>Value</span>, <span class='self'>Self</span>::<span class='ident'>Error</span><span class='op'>></span>
<span class='kw'>where</span> <span class='ident'>__V</span>: <span class='macro-nonterminal'>$</span><span class='kw'>crate</span>::<span class='macro-nonterminal'>de</span>::<span class='ident'>Visitor</span>
{
<span class='self'>self</span>.<span class='ident'>deserialize</span>(<span class='ident'>visitor</span>)
}
};
}
<span class='attribute'>#[<span class='ident'>doc</span>(<span class='ident'>hidden</span>)]</span>
<span class='attribute'>#[<span class='ident'>macro_export</span>]</span>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>forward_to_deserialize_helper</span> {
(<span class='ident'>bool</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_bool</span>()}
};
(<span class='ident'>u8</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_u8</span>()}
};
(<span class='ident'>u16</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_u16</span>()}
};
(<span class='ident'>u32</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_u32</span>()}
};
(<span class='ident'>u64</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_u64</span>()}
};
(<span class='ident'>i8</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_i8</span>()}
};
(<span class='ident'>i16</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_i16</span>()}
};
(<span class='ident'>i32</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_i32</span>()}
};
(<span class='ident'>i64</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_i64</span>()}
};
(<span class='ident'>f32</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_f32</span>()}
};
(<span class='ident'>f64</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_f64</span>()}
};
(<span class='ident'>char</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_char</span>()}
};
(<span class='ident'>str</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_str</span>()}
};
(<span class='ident'>string</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_string</span>()}
};
(<span class='ident'>unit</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_unit</span>()}
};
(<span class='ident'>option</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_option</span>()}
};
(<span class='ident'>seq</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_seq</span>()}
};
(<span class='ident'>seq_fixed_size</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_seq_fixed_size</span>(<span class='ident'>usize</span>)}
};
(<span class='ident'>bytes</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_bytes</span>()}
};
(<span class='ident'>byte_buf</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_byte_buf</span>()}
};
(<span class='ident'>map</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_map</span>()}
};
(<span class='ident'>unit_struct</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_unit_struct</span>(<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>)}
};
(<span class='ident'>newtype_struct</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_newtype_struct</span>(<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>)}
};
(<span class='ident'>tuple_struct</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_tuple_struct</span>(<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>, <span class='ident'>usize</span>)}
};
(<span class='kw'>struct</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_struct</span>(<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>, <span class='kw-2'>&</span><span class='lifetime'>'static</span> [<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>])}
};
(<span class='ident'>struct_field</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_struct_field</span>()}
};
(<span class='ident'>tuple</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_tuple</span>(<span class='ident'>usize</span>)}
};
(<span class='kw'>enum</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_enum</span>(<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>, <span class='kw-2'>&</span><span class='lifetime'>'static</span> [<span class='kw-2'>&</span><span class='lifetime'>'static</span> <span class='ident'>str</span>])}
};
(<span class='ident'>ignored_any</span>) <span class='op'>=></span> {
<span class='macro'>forward_to_deserialize_method</span><span class='macro'>!</span>{<span class='ident'>deserialize_ignored_any</span>()}
};
}
<span class='comment'>// Super explicit first paragraph because this shows up at the top level and</span>
<span class='comment'>// trips up people who are just looking for basic Serialize / Deserialize</span>
<span class='comment'>// documentation.</span>
<span class='comment'>//</span>
<span class='doccomment'>/// Helper macro when implementing the `Deserializer` part of a new data format</span>
<span class='doccomment'>/// for Serde.</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// Some `Deserializer` implementations for self-describing formats do not care</span>
<span class='doccomment'>/// what hint the `Visitor` gives them, they just want to blindly call the</span>
<span class='doccomment'>/// `Visitor` method corresponding to the data they can tell is in the input.</span>
<span class='doccomment'>/// This requires repetitive implementations of all the `Deserializer` trait</span>
<span class='doccomment'>/// methods.</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// ```rust</span>
<span class='doccomment'>/// # #[macro_use] extern crate serde;</span>
<span class='doccomment'>/// # use serde::de::{value, Deserializer, Visitor};</span>
<span class='doccomment'>/// # pub struct MyDeserializer;</span>
<span class='doccomment'>/// # impl Deserializer for MyDeserializer {</span>
<span class='doccomment'>/// # type Error = value::Error;</span>
<span class='doccomment'>/// # fn deserialize<V>(self, _: V) -> Result<V::Value, Self::Error></span>
<span class='doccomment'>/// # where V: Visitor</span>
<span class='doccomment'>/// # { unimplemented!() }</span>
<span class='doccomment'>/// #</span>
<span class='doccomment'>/// #[inline]</span>
<span class='doccomment'>/// fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error></span>
<span class='doccomment'>/// where V: Visitor</span>
<span class='doccomment'>/// {</span>
<span class='doccomment'>/// self.deserialize(visitor)</span>
<span class='doccomment'>/// }</span>
<span class='doccomment'>/// # forward_to_deserialize! {</span>
<span class='doccomment'>/// # u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit option</span>
<span class='doccomment'>/// # seq seq_fixed_size bytes byte_buf map unit_struct newtype_struct</span>
<span class='doccomment'>/// # tuple_struct struct struct_field tuple enum ignored_any</span>
<span class='doccomment'>/// # }</span>
<span class='doccomment'>/// # }</span>
<span class='doccomment'>/// # fn main() {}</span>
<span class='doccomment'>/// ```</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// The `forward_to_deserialize!` macro implements these simple forwarding</span>
<span class='doccomment'>/// methods so that they forward directly to `Deserializer::deserialize`. You</span>
<span class='doccomment'>/// can choose which methods to forward.</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// ```rust</span>
<span class='doccomment'>/// # #[macro_use] extern crate serde;</span>
<span class='doccomment'>/// # use serde::de::{value, Deserializer, Visitor};</span>
<span class='doccomment'>/// # pub struct MyDeserializer;</span>
<span class='doccomment'>/// impl Deserializer for MyDeserializer {</span>
<span class='doccomment'>/// # type Error = value::Error;</span>
<span class='doccomment'>/// fn deserialize<V>(self, visitor: V) -> Result<V::Value, Self::Error></span>
<span class='doccomment'>/// where V: Visitor</span>
<span class='doccomment'>/// {</span>
<span class='doccomment'>/// /* ... */</span>
<span class='doccomment'>/// # let _ = visitor;</span>
<span class='doccomment'>/// # unimplemented!()</span>
<span class='doccomment'>/// }</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// forward_to_deserialize! {</span>
<span class='doccomment'>/// bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit option</span>
<span class='doccomment'>/// seq seq_fixed_size bytes byte_buf map unit_struct newtype_struct</span>
<span class='doccomment'>/// tuple_struct struct struct_field tuple enum ignored_any</span>
<span class='doccomment'>/// }</span>
<span class='doccomment'>/// }</span>
<span class='doccomment'>/// # fn main() {}</span>
<span class='doccomment'>/// ```</span>
<span class='attribute'>#[<span class='ident'>macro_export</span>]</span>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>forward_to_deserialize</span> {
($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span>:<span class='ident'>ident</span>)<span class='kw-2'>*</span>) <span class='op'>=></span> {
$(<span class='macro'>forward_to_deserialize_helper</span><span class='macro'>!</span>{<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>func</span>})<span class='op'>*</span>
};
}
<span class='doccomment'>/// Seralize the `$value` that implements Display as a string,</span>
<span class='doccomment'>/// when that string is statically known to never have more than</span>
<span class='doccomment'>/// a constant `$MAX_LEN` bytes.</span>
<span class='doccomment'>///</span>
<span class='doccomment'>/// Panics if the Display impl tries to write more than `$MAX_LEN` bytes.</span>
<span class='attribute'>#[<span class='ident'>cfg</span>(<span class='ident'>feature</span> <span class='op'>=</span> <span class='string'>"std"</span>)]</span>
<span class='comment'>// Not exported</span>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>serialize_display_bounded_length</span> {
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>value</span>: <span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>MAX_LEN</span>: <span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>serializer</span>: <span class='ident'>expr</span>) <span class='op'>=></span> {
{
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>io</span>::<span class='ident'>Write</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>buffer</span>: [<span class='ident'>u8</span>; <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>MAX_LEN</span>] <span class='op'>=</span> <span class='kw'>unsafe</span> { ::<span class='ident'>std</span>::<span class='ident'>mem</span>::<span class='ident'>uninitialized</span>() };
<span class='kw'>let</span> <span class='ident'>remaining_len</span>;
{
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>remaining</span> <span class='op'>=</span> <span class='kw-2'>&</span><span class='kw-2'>mut</span> <span class='ident'>buffer</span>[..];
<span class='macro'>write</span><span class='macro'>!</span>(<span class='ident'>remaining</span>, <span class='string'>"{}"</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>value</span>).<span class='ident'>unwrap</span>();
<span class='ident'>remaining_len</span> <span class='op'>=</span> <span class='ident'>remaining</span>.<span class='ident'>len</span>()
}
<span class='kw'>let</span> <span class='ident'>written_len</span> <span class='op'>=</span> <span class='ident'>buffer</span>.<span class='ident'>len</span>() <span class='op'>-</span> <span class='ident'>remaining_len</span>;
<span class='kw'>let</span> <span class='ident'>written</span> <span class='op'>=</span> <span class='kw-2'>&</span><span class='ident'>buffer</span>[..<span class='ident'>written_len</span>];
<span class='comment'>// write! only provides std::fmt::Formatter to Display implementations,</span>
<span class='comment'>// which has methods write_str and write_char but no method to write arbitrary bytes.</span>
<span class='comment'>// Therefore, `written` is well-formed in UTF-8.</span>
<span class='kw'>let</span> <span class='ident'>written_str</span> <span class='op'>=</span> <span class='kw'>unsafe</span> {
::<span class='ident'>std</span>::<span class='ident'>str</span>::<span class='ident'>from_utf8_unchecked</span>(<span class='ident'>written</span>)
};
<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>serializer</span>.<span class='ident'>serialize_str</span>(<span class='ident'>written_str</span>)
}
}
}
</pre>
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