Trait quote::ToTokens

source · 
pub trait ToTokens {
    fn to_tokens(&self, tokens: &mut TokenStream);

    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§

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§

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.

Examples found in repository?
src/to_tokens.rs (line 73)
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    fn into_token_stream(self) -> TokenStream
    where
        Self: Sized,
    {
        self.to_token_stream()
    }

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.

Examples found in repository?
src/spanned.rs (line 16)
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    fn __span(&self) -> Span {
        join_spans(self.into_token_stream())
    }

Implementations on Foreign Types§

Implementors§