pub trait ToTokens {
// Required method
fn to_tokens(&self, tokens: &mut TokenStream);
// Provided methods
fn to_token_stream(&self) -> TokenStream { ... }
fn into_token_stream(self) -> TokenStream
where Self: Sized { ... }
}Expand description
Types that can be interpolated inside a quote! invocation.
Required Methods§
Sourcefn to_tokens(&self, tokens: &mut TokenStream)
fn to_tokens(&self, tokens: &mut TokenStream)
Write self to the given TokenStream.
The token append methods provided by the TokenStreamExt extension
trait may be useful for implementing ToTokens.
§Example
Example implementation for a struct representing Rust paths like
std::cmp::PartialEq:
use proc_macro2::{TokenTree, Spacing, Span, Punct, TokenStream};
use quote::{TokenStreamExt, ToTokens};
pub struct Path {
pub global: bool,
pub segments: Vec<PathSegment>,
}
impl ToTokens for Path {
fn to_tokens(&self, tokens: &mut TokenStream) {
for (i, segment) in self.segments.iter().enumerate() {
if i > 0 || self.global {
// Double colon `::`
tokens.append(Punct::new(':', Spacing::Joint));
tokens.append(Punct::new(':', Spacing::Alone));
}
segment.to_tokens(tokens);
}
}
}Provided Methods§
Sourcefn to_token_stream(&self) -> TokenStream
fn to_token_stream(&self) -> TokenStream
Convert self directly into a TokenStream object.
This method is implicitly implemented using to_tokens, and acts as a
convenience method for consumers of the ToTokens trait.
Sourcefn into_token_stream(self) -> TokenStreamwhere
Self: Sized,
fn into_token_stream(self) -> TokenStreamwhere
Self: Sized,
Convert self directly into a TokenStream object.
This method is implicitly implemented using to_tokens, and acts as a
convenience method for consumers of the ToTokens trait.
Dyn Compatibility§
This trait is dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety".