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Diffstat (limited to 'syn/src/mac.rs')
| -rw-r--r-- | syn/src/mac.rs | 239 |
1 files changed, 0 insertions, 239 deletions
diff --git a/syn/src/mac.rs b/syn/src/mac.rs deleted file mode 100644 index 6c3dcae..0000000 --- a/syn/src/mac.rs +++ /dev/null @@ -1,239 +0,0 @@ -use super::*; -use crate::token::{Brace, Bracket, Paren}; -use proc_macro2::TokenStream; -#[cfg(feature = "parsing")] -use proc_macro2::{Delimiter, Span, TokenTree}; - -#[cfg(feature = "parsing")] -use crate::parse::{Parse, ParseStream, Parser, Result}; -#[cfg(feature = "extra-traits")] -use crate::tt::TokenStreamHelper; -#[cfg(feature = "extra-traits")] -use std::hash::{Hash, Hasher}; - -ast_struct! { - /// A macro invocation: `println!("{}", mac)`. - /// - /// *This type is available if Syn is built with the `"derive"` or `"full"` - /// feature.* - pub struct Macro #manual_extra_traits { - pub path: Path, - pub bang_token: Token![!], - pub delimiter: MacroDelimiter, - pub tokens: TokenStream, - } -} - -ast_enum! { - /// A grouping token that surrounds a macro body: `m!(...)` or `m!{...}` or `m![...]`. - /// - /// *This type is available if Syn is built with the `"derive"` or `"full"` - /// feature.* - pub enum MacroDelimiter { - Paren(Paren), - Brace(Brace), - Bracket(Bracket), - } -} - -#[cfg(feature = "extra-traits")] -impl Eq for Macro {} - -#[cfg(feature = "extra-traits")] -impl PartialEq for Macro { - fn eq(&self, other: &Self) -> bool { - self.path == other.path - && self.bang_token == other.bang_token - && self.delimiter == other.delimiter - && TokenStreamHelper(&self.tokens) == TokenStreamHelper(&other.tokens) - } -} - -#[cfg(feature = "extra-traits")] -impl Hash for Macro { - fn hash<H>(&self, state: &mut H) - where - H: Hasher, - { - self.path.hash(state); - self.bang_token.hash(state); - self.delimiter.hash(state); - TokenStreamHelper(&self.tokens).hash(state); - } -} - -#[cfg(feature = "parsing")] -fn delimiter_span(delimiter: &MacroDelimiter) -> Span { - match delimiter { - MacroDelimiter::Paren(token) => token.span, - MacroDelimiter::Brace(token) => token.span, - MacroDelimiter::Bracket(token) => token.span, - } -} - -impl Macro { - /// Parse the tokens within the macro invocation's delimiters into a syntax - /// tree. - /// - /// This is equivalent to `syn::parse2::<T>(mac.tokens)` except that it - /// produces a more useful span when `tokens` is empty. - /// - /// # Example - /// - /// ``` - /// use syn::{parse_quote, Expr, ExprLit, Ident, Lit, LitStr, Macro, Token}; - /// use syn::ext::IdentExt; - /// use syn::parse::{Error, Parse, ParseStream, Result}; - /// use syn::punctuated::Punctuated; - /// - /// // The arguments expected by libcore's format_args macro, and as a - /// // result most other formatting and printing macros like println. - /// // - /// // println!("{} is {number:.prec$}", "x", prec=5, number=0.01) - /// struct FormatArgs { - /// format_string: Expr, - /// positional_args: Vec<Expr>, - /// named_args: Vec<(Ident, Expr)>, - /// } - /// - /// impl Parse for FormatArgs { - /// fn parse(input: ParseStream) -> Result<Self> { - /// let format_string: Expr; - /// let mut positional_args = Vec::new(); - /// let mut named_args = Vec::new(); - /// - /// format_string = input.parse()?; - /// while !input.is_empty() { - /// input.parse::<Token![,]>()?; - /// if input.is_empty() { - /// break; - /// } - /// if input.peek(Ident::peek_any) && input.peek2(Token![=]) { - /// while !input.is_empty() { - /// let name: Ident = input.call(Ident::parse_any)?; - /// input.parse::<Token![=]>()?; - /// let value: Expr = input.parse()?; - /// named_args.push((name, value)); - /// if input.is_empty() { - /// break; - /// } - /// input.parse::<Token![,]>()?; - /// } - /// break; - /// } - /// positional_args.push(input.parse()?); - /// } - /// - /// Ok(FormatArgs { - /// format_string, - /// positional_args, - /// named_args, - /// }) - /// } - /// } - /// - /// // Extract the first argument, the format string literal, from an - /// // invocation of a formatting or printing macro. - /// fn get_format_string(m: &Macro) -> Result<LitStr> { - /// let args: FormatArgs = m.parse_body()?; - /// match args.format_string { - /// Expr::Lit(ExprLit { lit: Lit::Str(lit), .. }) => Ok(lit), - /// other => { - /// // First argument was not a string literal expression. - /// // Maybe something like: println!(concat!(...), ...) - /// Err(Error::new_spanned(other, "format string must be a string literal")) - /// } - /// } - /// } - /// - /// fn main() { - /// let invocation = parse_quote! { - /// println!("{:?}", Instant::now()) - /// }; - /// let lit = get_format_string(&invocation).unwrap(); - /// assert_eq!(lit.value(), "{:?}"); - /// } - /// ``` - #[cfg(feature = "parsing")] - pub fn parse_body<T: Parse>(&self) -> Result<T> { - self.parse_body_with(T::parse) - } - - /// Parse the tokens within the macro invocation's delimiters using the - /// given parser. - #[cfg(feature = "parsing")] - pub fn parse_body_with<F: Parser>(&self, parser: F) -> Result<F::Output> { - // TODO: see if we can get a group.span_close() span in here as the - // scope, rather than the span of the whole group. - let scope = delimiter_span(&self.delimiter); - crate::parse::parse_scoped(parser, scope, self.tokens.clone()) - } -} - -#[cfg(feature = "parsing")] -pub fn parse_delimiter(input: ParseStream) -> Result<(MacroDelimiter, TokenStream)> { - input.step(|cursor| { - if let Some((TokenTree::Group(g), rest)) = cursor.token_tree() { - let span = g.span(); - let delimiter = match g.delimiter() { - Delimiter::Parenthesis => MacroDelimiter::Paren(Paren(span)), - Delimiter::Brace => MacroDelimiter::Brace(Brace(span)), - Delimiter::Bracket => MacroDelimiter::Bracket(Bracket(span)), - Delimiter::None => { - return Err(cursor.error("expected delimiter")); - } - }; - Ok(((delimiter, g.stream()), rest)) - } else { - Err(cursor.error("expected delimiter")) - } - }) -} - -#[cfg(feature = "parsing")] -pub mod parsing { - use super::*; - - use crate::parse::{Parse, ParseStream, Result}; - - impl Parse for Macro { - fn parse(input: ParseStream) -> Result<Self> { - let tokens; - Ok(Macro { - path: input.call(Path::parse_mod_style)?, - bang_token: input.parse()?, - delimiter: { - let (delimiter, content) = parse_delimiter(input)?; - tokens = content; - delimiter - }, - tokens, - }) - } - } -} - -#[cfg(feature = "printing")] -mod printing { - use super::*; - use proc_macro2::TokenStream; - use quote::ToTokens; - - impl ToTokens for Macro { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.path.to_tokens(tokens); - self.bang_token.to_tokens(tokens); - match &self.delimiter { - MacroDelimiter::Paren(paren) => { - paren.surround(tokens, |tokens| self.tokens.to_tokens(tokens)); - } - MacroDelimiter::Brace(brace) => { - brace.surround(tokens, |tokens| self.tokens.to_tokens(tokens)); - } - MacroDelimiter::Bracket(bracket) => { - bracket.surround(tokens, |tokens| self.tokens.to_tokens(tokens)); - } - } - } - } -} |