use super::ToTokens;
use proc_macro2::{TokenStream, TokenTree};
pub trait TokenStreamExt: private::Sealed {
fn append<U>(&mut self, token: U)
where
U: Into<TokenTree>;
fn append_all<T, I>(&mut self, iter: I)
where
T: ToTokens,
I: IntoIterator<Item = T>;
fn append_separated<T, I, U>(&mut self, iter: I, op: U)
where
T: ToTokens,
I: IntoIterator<Item = T>,
U: ToTokens;
fn append_terminated<T, I, U>(&mut self, iter: I, term: U)
where
T: ToTokens,
I: IntoIterator<Item = T>,
U: ToTokens;
}
impl TokenStreamExt for TokenStream {
fn append<U>(&mut self, token: U)
where
U: Into<TokenTree>,
{
self.extend(Some(token.into()));
}
fn append_all<T, I>(&mut self, iter: I)
where
T: ToTokens,
I: IntoIterator<Item = T>,
{
for token in iter {
token.to_tokens(self);
}
}
fn append_separated<T, I, U>(&mut self, iter: I, op: U)
where
T: ToTokens,
I: IntoIterator<Item = T>,
U: ToTokens,
{
for (i, token) in iter.into_iter().enumerate() {
if i > 0 {
op.to_tokens(self);
}
token.to_tokens(self);
}
}
fn append_terminated<T, I, U>(&mut self, iter: I, term: U)
where
T: ToTokens,
I: IntoIterator<Item = T>,
U: ToTokens,
{
for token in iter {
token.to_tokens(self);
term.to_tokens(self);
}
}
}
mod private {
use proc_macro2::TokenStream;
pub trait Sealed {}
impl Sealed for TokenStream {}
}