58b3af4c29
The following changes are included: - Delete per-file license notices at the top of each file. - Delete the first paragraph of LICENSE-MIT (an inaccurate pseudo-copyright line), leaving only the text of the MIT license. Nothing about the license of Serde code has changed, only our understanding of how to correctly communicate that license has changed. This mirrors an equivalent change being applied in the rust-lang/rust repository.
75 lines
2.1 KiB
Rust
75 lines
2.1 KiB
Rust
use proc_macro2::TokenStream;
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use quote::ToTokens;
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use syn::token;
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pub enum Fragment {
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/// Tokens that can be used as an expression.
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Expr(TokenStream),
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/// Tokens that can be used inside a block. The surrounding curly braces are
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/// not part of these tokens.
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Block(TokenStream),
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}
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macro_rules! quote_expr {
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($($tt:tt)*) => {
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$crate::fragment::Fragment::Expr(quote!($($tt)*))
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}
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}
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macro_rules! quote_block {
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($($tt:tt)*) => {
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$crate::fragment::Fragment::Block(quote!($($tt)*))
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}
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}
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/// Interpolate a fragment in place of an expression. This involves surrounding
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/// Block fragments in curly braces.
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pub struct Expr(pub Fragment);
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impl ToTokens for Expr {
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fn to_tokens(&self, out: &mut TokenStream) {
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match self.0 {
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Fragment::Expr(ref expr) => expr.to_tokens(out),
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Fragment::Block(ref block) => {
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token::Brace::default().surround(out, |out| block.to_tokens(out));
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}
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}
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}
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}
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/// Interpolate a fragment as the statements of a block.
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pub struct Stmts(pub Fragment);
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impl ToTokens for Stmts {
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fn to_tokens(&self, out: &mut TokenStream) {
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match self.0 {
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Fragment::Expr(ref expr) => expr.to_tokens(out),
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Fragment::Block(ref block) => block.to_tokens(out),
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}
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}
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}
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/// Interpolate a fragment as the value part of a `match` expression. This
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/// involves putting a comma after expressions and curly braces around blocks.
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pub struct Match(pub Fragment);
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impl ToTokens for Match {
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fn to_tokens(&self, out: &mut TokenStream) {
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match self.0 {
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Fragment::Expr(ref expr) => {
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expr.to_tokens(out);
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<Token![,]>::default().to_tokens(out);
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}
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Fragment::Block(ref block) => {
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token::Brace::default().surround(out, |out| block.to_tokens(out));
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}
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}
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}
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}
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impl AsRef<TokenStream> for Fragment {
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fn as_ref(&self) -> &TokenStream {
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match *self {
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Fragment::Expr(ref expr) => expr,
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Fragment::Block(ref block) => block,
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}
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}
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}
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