tamer: Use TokenStream trait alias where applicable

Simple replacement to improve readability.

tamer/src/ir/xir/iter.rs

@@ -25,7 +25,7 @@
 //!   - [`elem_wrap`] wraps a token stream iterator as the body of an
 //!       element of the given name.
 
-use super::{QName, Token};
+use super::{QName, Token, TokenStream};
 use crate::span::Span;
 use std::iter::{once, Chain, Once};
 
@@ -42,7 +42,7 @@ use std::iter::{once, Chain, Once};
 pub fn elem_wrap<S, I>(name: QName, span: S, inner: I) -> ElemWrapIter<I>
 where
     S: Into<(Span, Span)>,
-    I: Iterator<Item = Token>,
+    I: TokenStream,
 {
     let twospan: (Span, Span) = span.into();
 
@@ -59,18 +59,18 @@ where
 ///   iterator.
 ///
 /// See [`elem_wrap`] to construct this iterator.
-pub struct ElemWrapIter<I: Iterator<Item = Token>>(
+pub struct ElemWrapIter<I: TokenStream>(
     Chain<Chain<Once<Token>, I>, Once<Token>>,
 );
 
-impl<I: Iterator<Item = Token>> ElemWrapIter<I> {
+impl<I: TokenStream> ElemWrapIter<I> {
     #[inline]
     fn new(open: Token, inner: I, close: Token) -> Self {
         Self(once(open).chain(inner).chain(once(close)))
     }
 }
 
-impl<I: Iterator<Item = Token>> Iterator for ElemWrapIter<I> {
+impl<I: TokenStream> Iterator for ElemWrapIter<I> {
     type Item = Token;
 
     #[inline]

tamer/src/ir/xir/tree.rs

@@ -191,7 +191,7 @@
 //! For more information,
 //!   see [`AttrParts`].
 
-use super::{AttrValue, QName, Text, Token, TokenResultStream};
+use super::{AttrValue, QName, Text, Token, TokenResultStream, TokenStream};
 use crate::span::Span;
 use std::{fmt::Display, mem::take};
 
@@ -849,7 +849,7 @@ pub fn parse(state: &mut ParserState, tok: Token) -> Option<Result<Parsed>> {
 /// let parser = parser_from(token_stream);
 /// ```
 pub fn parser_from(
-    toks: impl Iterator<Item = Token>,
+    toks: impl TokenStream,
 ) -> impl Iterator<Item = Result<Tree>> {
     toks.scan(ParserState::new(), parse)
         .filter_map(|parsed| match parsed {

tamer/src/ir/xir/writer.rs

@@ -19,7 +19,7 @@
 
 //! Lower XIR stream into an XML byte stream via [`Write`].
 
-use super::{Error as XirError, QName, Token};
+use super::{Error as XirError, QName, Token, TokenStream};
 use crate::ir::xir::{AttrValue, Text};
 use crate::sym::GlobalSymbolResolve;
 use std::io::{Error as IoError, Write};
@@ -318,7 +318,7 @@ impl XmlWriter for Token {
     }
 }
 
-impl<I: Iterator<Item = Token>> XmlWriter for I {
+impl<I: TokenStream> XmlWriter for I {
     fn write<W: Write>(
         mut self,
         sink: &mut W,