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</pre><pre class="rust"><code><span class="kw">use super</span>::<span class="kw-2">*</span>;
<span class="kw">use </span><span class="kw">crate</span>::punctuated::Punctuated;
<span class="macro">ast_struct! </span>{
<span class="doccomment">/// Data structure sent to a `proc_macro_derive` macro.
</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;derive&quot;</span>)))]
</span><span class="kw">pub struct </span>DeriveInput {
<span class="kw">pub </span>attrs: Vec&lt;Attribute&gt;,
<span class="kw">pub </span>vis: Visibility,
<span class="kw">pub </span>ident: Ident,
<span class="kw">pub </span>generics: Generics,
<span class="kw">pub </span>data: Data,
}
}
<span class="macro">ast_enum! </span>{
<span class="doccomment">/// The storage of a struct, enum or union data structure.
///
/// # Syntax tree enum
///
/// This type is a [syntax tree enum].
///
/// [syntax tree enum]: Expr#syntax-tree-enums
</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;derive&quot;</span>)))]
</span><span class="kw">pub enum </span>Data {
Struct(DataStruct),
Enum(DataEnum),
Union(DataUnion),
}
}
<span class="macro">ast_struct! </span>{
<span class="doccomment">/// A struct input to a `proc_macro_derive` macro.
</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;derive&quot;</span>)))]
</span><span class="kw">pub struct </span>DataStruct {
<span class="kw">pub </span>struct_token: <span class="macro">Token!</span>[<span class="kw">struct</span>],
<span class="kw">pub </span>fields: Fields,
<span class="kw">pub </span>semi_token: <span class="prelude-ty">Option</span>&lt;<span class="macro">Token!</span>[;]&gt;,
}
}
<span class="macro">ast_struct! </span>{
<span class="doccomment">/// An enum input to a `proc_macro_derive` macro.
</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;derive&quot;</span>)))]
</span><span class="kw">pub struct </span>DataEnum {
<span class="kw">pub </span>enum_token: <span class="macro">Token!</span>[<span class="kw">enum</span>],
<span class="kw">pub </span>brace_token: token::Brace,
<span class="kw">pub </span>variants: Punctuated&lt;Variant, <span class="macro">Token!</span>[,]&gt;,
}
}
<span class="macro">ast_struct! </span>{
<span class="doccomment">/// An untagged union input to a `proc_macro_derive` macro.
</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;derive&quot;</span>)))]
</span><span class="kw">pub struct </span>DataUnion {
<span class="kw">pub </span>union_token: <span class="macro">Token!</span>[union],
<span class="kw">pub </span>fields: FieldsNamed,
}
}
<span class="attribute">#[cfg(feature = <span class="string">&quot;parsing&quot;</span>)]
</span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">mod </span>parsing {
<span class="kw">use super</span>::<span class="kw-2">*</span>;
<span class="kw">use </span><span class="kw">crate</span>::parse::{Parse, ParseStream, <span class="prelude-ty">Result</span>};
<span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;parsing&quot;</span>)))]
</span><span class="kw">impl </span>Parse <span class="kw">for </span>DeriveInput {
<span class="kw">fn </span>parse(input: ParseStream) -&gt; <span class="prelude-ty">Result</span>&lt;<span class="self">Self</span>&gt; {
<span class="kw">let </span>attrs = input.call(Attribute::parse_outer)<span class="question-mark">?</span>;
<span class="kw">let </span>vis = input.parse::&lt;Visibility&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>lookahead = input.lookahead1();
<span class="kw">if </span>lookahead.peek(<span class="macro">Token!</span>[<span class="kw">struct</span>]) {
<span class="kw">let </span>struct_token = input.parse::&lt;<span class="macro">Token!</span>[<span class="kw">struct</span>]&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>ident = input.parse::&lt;Ident&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>generics = input.parse::&lt;Generics&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>(where_clause, fields, semi) = data_struct(input)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(DeriveInput {
attrs,
vis,
ident,
generics: Generics {
where_clause,
..generics
},
data: Data::Struct(DataStruct {
struct_token,
fields,
semi_token: semi,
}),
})
} <span class="kw">else if </span>lookahead.peek(<span class="macro">Token!</span>[<span class="kw">enum</span>]) {
<span class="kw">let </span>enum_token = input.parse::&lt;<span class="macro">Token!</span>[<span class="kw">enum</span>]&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>ident = input.parse::&lt;Ident&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>generics = input.parse::&lt;Generics&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>(where_clause, brace, variants) = data_enum(input)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(DeriveInput {
attrs,
vis,
ident,
generics: Generics {
where_clause,
..generics
},
data: Data::Enum(DataEnum {
enum_token,
brace_token: brace,
variants,
}),
})
} <span class="kw">else if </span>lookahead.peek(<span class="macro">Token!</span>[union]) {
<span class="kw">let </span>union_token = input.parse::&lt;<span class="macro">Token!</span>[union]&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>ident = input.parse::&lt;Ident&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>generics = input.parse::&lt;Generics&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>(where_clause, fields) = data_union(input)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(DeriveInput {
attrs,
vis,
ident,
generics: Generics {
where_clause,
..generics
},
data: Data::Union(DataUnion {
union_token,
fields,
}),
})
} <span class="kw">else </span>{
<span class="prelude-val">Err</span>(lookahead.error())
}
}
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>data_struct(
input: ParseStream,
) -&gt; <span class="prelude-ty">Result</span>&lt;(<span class="prelude-ty">Option</span>&lt;WhereClause&gt;, Fields, <span class="prelude-ty">Option</span>&lt;<span class="macro">Token!</span>[;]&gt;)&gt; {
<span class="kw">let </span><span class="kw-2">mut </span>lookahead = input.lookahead1();
<span class="kw">let </span><span class="kw-2">mut </span>where_clause = <span class="prelude-val">None</span>;
<span class="kw">if </span>lookahead.peek(<span class="macro">Token!</span>[<span class="kw">where</span>]) {
where_clause = <span class="prelude-val">Some</span>(input.parse()<span class="question-mark">?</span>);
lookahead = input.lookahead1();
}
<span class="kw">if </span>where_clause.is_none() &amp;&amp; lookahead.peek(token::Paren) {
<span class="kw">let </span>fields = input.parse()<span class="question-mark">?</span>;
lookahead = input.lookahead1();
<span class="kw">if </span>lookahead.peek(<span class="macro">Token!</span>[<span class="kw">where</span>]) {
where_clause = <span class="prelude-val">Some</span>(input.parse()<span class="question-mark">?</span>);
lookahead = input.lookahead1();
}
<span class="kw">if </span>lookahead.peek(<span class="macro">Token!</span>[;]) {
<span class="kw">let </span>semi = input.parse()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>((where_clause, Fields::Unnamed(fields), <span class="prelude-val">Some</span>(semi)))
} <span class="kw">else </span>{
<span class="prelude-val">Err</span>(lookahead.error())
}
} <span class="kw">else if </span>lookahead.peek(token::Brace) {
<span class="kw">let </span>fields = input.parse()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>((where_clause, Fields::Named(fields), <span class="prelude-val">None</span>))
} <span class="kw">else if </span>lookahead.peek(<span class="macro">Token!</span>[;]) {
<span class="kw">let </span>semi = input.parse()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>((where_clause, Fields::Unit, <span class="prelude-val">Some</span>(semi)))
} <span class="kw">else </span>{
<span class="prelude-val">Err</span>(lookahead.error())
}
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>data_enum(
input: ParseStream,
) -&gt; <span class="prelude-ty">Result</span>&lt;(
<span class="prelude-ty">Option</span>&lt;WhereClause&gt;,
token::Brace,
Punctuated&lt;Variant, <span class="macro">Token!</span>[,]&gt;,
)&gt; {
<span class="kw">let </span>where_clause = input.parse()<span class="question-mark">?</span>;
<span class="kw">let </span>content;
<span class="kw">let </span>brace = <span class="macro">braced!</span>(content <span class="kw">in </span>input);
<span class="kw">let </span>variants = content.parse_terminated(Variant::parse, <span class="macro">Token!</span>[,])<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>((where_clause, brace, variants))
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>data_union(input: ParseStream) -&gt; <span class="prelude-ty">Result</span>&lt;(<span class="prelude-ty">Option</span>&lt;WhereClause&gt;, FieldsNamed)&gt; {
<span class="kw">let </span>where_clause = input.parse()<span class="question-mark">?</span>;
<span class="kw">let </span>fields = input.parse()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>((where_clause, fields))
}
}
<span class="attribute">#[cfg(feature = <span class="string">&quot;printing&quot;</span>)]
</span><span class="kw">mod </span>printing {
<span class="kw">use super</span>::<span class="kw-2">*</span>;
<span class="kw">use </span><span class="kw">crate</span>::attr::FilterAttrs;
<span class="kw">use </span><span class="kw">crate</span>::print::TokensOrDefault;
<span class="kw">use </span>proc_macro2::TokenStream;
<span class="kw">use </span>quote::ToTokens;
<span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">&quot;printing&quot;</span>)))]
</span><span class="kw">impl </span>ToTokens <span class="kw">for </span>DeriveInput {
<span class="kw">fn </span>to_tokens(<span class="kw-2">&amp;</span><span class="self">self</span>, tokens: <span class="kw-2">&amp;mut </span>TokenStream) {
<span class="kw">for </span>attr <span class="kw">in </span><span class="self">self</span>.attrs.outer() {
attr.to_tokens(tokens);
}
<span class="self">self</span>.vis.to_tokens(tokens);
<span class="kw">match </span><span class="kw-2">&amp;</span><span class="self">self</span>.data {
Data::Struct(d) =&gt; d.struct_token.to_tokens(tokens),
Data::Enum(d) =&gt; d.enum_token.to_tokens(tokens),
Data::Union(d) =&gt; d.union_token.to_tokens(tokens),
}
<span class="self">self</span>.ident.to_tokens(tokens);
<span class="self">self</span>.generics.to_tokens(tokens);
<span class="kw">match </span><span class="kw-2">&amp;</span><span class="self">self</span>.data {
Data::Struct(data) =&gt; <span class="kw">match </span><span class="kw-2">&amp;</span>data.fields {
Fields::Named(fields) =&gt; {
<span class="self">self</span>.generics.where_clause.to_tokens(tokens);
fields.to_tokens(tokens);
}
Fields::Unnamed(fields) =&gt; {
fields.to_tokens(tokens);
<span class="self">self</span>.generics.where_clause.to_tokens(tokens);
TokensOrDefault(<span class="kw-2">&amp;</span>data.semi_token).to_tokens(tokens);
}
Fields::Unit =&gt; {
<span class="self">self</span>.generics.where_clause.to_tokens(tokens);
TokensOrDefault(<span class="kw-2">&amp;</span>data.semi_token).to_tokens(tokens);
}
},
Data::Enum(data) =&gt; {
<span class="self">self</span>.generics.where_clause.to_tokens(tokens);
data.brace_token.surround(tokens, |tokens| {
data.variants.to_tokens(tokens);
});
}
Data::Union(data) =&gt; {
<span class="self">self</span>.generics.where_clause.to_tokens(tokens);
data.fields.to_tokens(tokens);
}
}
}
}
}
</code></pre></div>
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