#[cfg(feature = "extra-traits")]
use std::fmt::{self, Debug};
#[cfg(feature = "extra-traits")]
use std::hash::{Hash, Hasher};
#[cfg(any(feature = "full", feature = "derive"))]
use std::iter;
use std::iter::FromIterator;
use std::ops::{Index, IndexMut};
use std::option;
use std::slice;
use std::vec;
#[cfg(feature = "parsing")]
use crate::parse::{Parse, ParseStream, Result};
#[cfg(feature = "parsing")]
use crate::token::Token;
pub struct Punctuated<T, P> {
inner: Vec<(T, P)>,
last: Option<Box<T>>,
}
impl<T, P> Punctuated<T, P> {
#[cfg(not(syn_no_const_vec_new))]
pub const fn new() -> Self {
Punctuated {
inner: Vec::new(),
last: None,
}
}
#[cfg(syn_no_const_vec_new)]
pub fn new() -> Self {
Punctuated {
inner: Vec::new(),
last: None,
}
}
pub fn is_empty(&self) -> bool {
self.inner.len() == 0 && self.last.is_none()
}
pub fn len(&self) -> usize {
self.inner.len() + if self.last.is_some() { 1 } else { 0 }
}
pub fn first(&self) -> Option<&T> {
self.iter().next()
}
pub fn first_mut(&mut self) -> Option<&mut T> {
self.iter_mut().next()
}
pub fn last(&self) -> Option<&T> {
self.iter().next_back()
}
pub fn last_mut(&mut self) -> Option<&mut T> {
self.iter_mut().next_back()
}
pub fn iter(&self) -> Iter<T> {
Iter {
inner: Box::new(PrivateIter {
inner: self.inner.iter(),
last: self.last.as_ref().map(Box::as_ref).into_iter(),
}),
}
}
pub fn iter_mut(&mut self) -> IterMut<T> {
IterMut {
inner: Box::new(PrivateIterMut {
inner: self.inner.iter_mut(),
last: self.last.as_mut().map(Box::as_mut).into_iter(),
}),
}
}
pub fn pairs(&self) -> Pairs<T, P> {
Pairs {
inner: self.inner.iter(),
last: self.last.as_ref().map(Box::as_ref).into_iter(),
}
}
pub fn pairs_mut(&mut self) -> PairsMut<T, P> {
PairsMut {
inner: self.inner.iter_mut(),
last: self.last.as_mut().map(Box::as_mut).into_iter(),
}
}
pub fn into_pairs(self) -> IntoPairs<T, P> {
IntoPairs {
inner: self.inner.into_iter(),
last: self.last.map(|t| *t).into_iter(),
}
}
pub fn push_value(&mut self, value: T) {
assert!(
self.empty_or_trailing(),
"Punctuated::push_value: cannot push value if Punctuated is missing trailing punctuation",
);
self.last = Some(Box::new(value));
}
pub fn push_punct(&mut self, punctuation: P) {
assert!(
self.last.is_some(),
"Punctuated::push_punct: cannot push punctuation if Punctuated is empty or already has trailing punctuation",
);
let last = self.last.take().unwrap();
self.inner.push((*last, punctuation));
}
pub fn pop(&mut self) -> Option<Pair<T, P>> {
if self.last.is_some() {
self.last.take().map(|t| Pair::End(*t))
} else {
self.inner.pop().map(|(t, d)| Pair::Punctuated(t, d))
}
}
pub fn trailing_punct(&self) -> bool {
self.last.is_none() && !self.is_empty()
}
pub fn empty_or_trailing(&self) -> bool {
self.last.is_none()
}
pub fn push(&mut self, value: T)
where
P: Default,
{
if !self.empty_or_trailing() {
self.push_punct(Default::default());
}
self.push_value(value);
}
pub fn insert(&mut self, index: usize, value: T)
where
P: Default,
{
assert!(
index <= self.len(),
"Punctuated::insert: index out of range",
);
if index == self.len() {
self.push(value);
} else {
self.inner.insert(index, (value, Default::default()));
}
}
pub fn clear(&mut self) {
self.inner.clear();
self.last = None;
}
#[cfg(feature = "parsing")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
pub fn parse_terminated(input: ParseStream) -> Result<Self>
where
T: Parse,
P: Parse,
{
Self::parse_terminated_with(input, T::parse)
}
#[cfg(feature = "parsing")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
pub fn parse_terminated_with(
input: ParseStream,
parser: fn(ParseStream) -> Result<T>,
) -> Result<Self>
where
P: Parse,
{
let mut punctuated = Punctuated::new();
loop {
if input.is_empty() {
break;
}
let value = parser(input)?;
punctuated.push_value(value);
if input.is_empty() {
break;
}
let punct = input.parse()?;
punctuated.push_punct(punct);
}
Ok(punctuated)
}
#[cfg(feature = "parsing")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
pub fn parse_separated_nonempty(input: ParseStream) -> Result<Self>
where
T: Parse,
P: Token + Parse,
{
Self::parse_separated_nonempty_with(input, T::parse)
}
#[cfg(feature = "parsing")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
pub fn parse_separated_nonempty_with(
input: ParseStream,
parser: fn(ParseStream) -> Result<T>,
) -> Result<Self>
where
P: Token + Parse,
{
let mut punctuated = Punctuated::new();
loop {
let value = parser(input)?;
punctuated.push_value(value);
if !P::peek(input.cursor()) {
break;
}
let punct = input.parse()?;
punctuated.push_punct(punct);
}
Ok(punctuated)
}
}
#[cfg(feature = "clone-impls")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))]
impl<T, P> Clone for Punctuated<T, P>
where
T: Clone,
P: Clone,
{
fn clone(&self) -> Self {
Punctuated {
inner: self.inner.clone(),
last: self.last.clone(),
}
}
}
#[cfg(feature = "extra-traits")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
impl<T, P> Eq for Punctuated<T, P>
where
T: Eq,
P: Eq,
{
}
#[cfg(feature = "extra-traits")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
impl<T, P> PartialEq for Punctuated<T, P>
where
T: PartialEq,
P: PartialEq,
{
fn eq(&self, other: &Self) -> bool {
let Punctuated { inner, last } = self;
*inner == other.inner && *last == other.last
}
}
#[cfg(feature = "extra-traits")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
impl<T, P> Hash for Punctuated<T, P>
where
T: Hash,
P: Hash,
{
fn hash<H: Hasher>(&self, state: &mut H) {
let Punctuated { inner, last } = self;
inner.hash(state);
last.hash(state);
}
}
#[cfg(feature = "extra-traits")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
impl<T: Debug, P: Debug> Debug for Punctuated<T, P> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut list = f.debug_list();
for (t, p) in &self.inner {
list.entry(t);
list.entry(p);
}
if let Some(last) = &self.last {
list.entry(last);
}
list.finish()
}
}
impl<T, P> FromIterator<T> for Punctuated<T, P>
where
P: Default,
{
fn from_iter<I: IntoIterator<Item = T>>(i: I) -> Self {
let mut ret = Punctuated::new();
ret.extend(i);
ret
}
}
impl<T, P> Extend<T> for Punctuated<T, P>
where
P: Default,
{
fn extend<I: IntoIterator<Item = T>>(&mut self, i: I) {
for value in i {
self.push(value);
}
}
}
impl<T, P> FromIterator<Pair<T, P>> for Punctuated<T, P> {
fn from_iter<I: IntoIterator<Item = Pair<T, P>>>(i: I) -> Self {
let mut ret = Punctuated::new();
ret.extend(i);
ret
}
}
impl<T, P> Extend<Pair<T, P>> for Punctuated<T, P> {
fn extend<I: IntoIterator<Item = Pair<T, P>>>(&mut self, i: I) {
assert!(
self.empty_or_trailing(),
"Punctuated::extend: Punctuated is not empty or does not have a trailing punctuation",
);
let mut nomore = false;
for pair in i {
if nomore {
panic!("Punctuated extended with items after a Pair::End");
}
match pair {
Pair::Punctuated(a, b) => self.inner.push((a, b)),
Pair::End(a) => {
self.last = Some(Box::new(a));
nomore = true;
}
}
}
}
}
impl<T, P> IntoIterator for Punctuated<T, P> {
type Item = T;
type IntoIter = IntoIter<T>;
fn into_iter(self) -> Self::IntoIter {
let mut elements = Vec::with_capacity(self.len());
elements.extend(self.inner.into_iter().map(|pair| pair.0));
elements.extend(self.last.map(|t| *t));
IntoIter {
inner: elements.into_iter(),
}
}
}
impl<'a, T, P> IntoIterator for &'a Punctuated<T, P> {
type Item = &'a T;
type IntoIter = Iter<'a, T>;
fn into_iter(self) -> Self::IntoIter {
Punctuated::iter(self)
}
}
impl<'a, T, P> IntoIterator for &'a mut Punctuated<T, P> {
type Item = &'a mut T;
type IntoIter = IterMut<'a, T>;
fn into_iter(self) -> Self::IntoIter {
Punctuated::iter_mut(self)
}
}
impl<T, P> Default for Punctuated<T, P> {
fn default() -> Self {
Punctuated::new()
}
}
pub struct Pairs<'a, T: 'a, P: 'a> {
inner: slice::Iter<'a, (T, P)>,
last: option::IntoIter<&'a T>,
}
impl<'a, T, P> Iterator for Pairs<'a, T, P> {
type Item = Pair<&'a T, &'a P>;
fn next(&mut self) -> Option<Self::Item> {
self.inner
.next()
.map(|(t, p)| Pair::Punctuated(t, p))
.or_else(|| self.last.next().map(Pair::End))
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<'a, T, P> DoubleEndedIterator for Pairs<'a, T, P> {
fn next_back(&mut self) -> Option<Self::Item> {
self.last
.next()
.map(Pair::End)
.or_else(|| self.inner.next_back().map(|(t, p)| Pair::Punctuated(t, p)))
}
}
impl<'a, T, P> ExactSizeIterator for Pairs<'a, T, P> {
fn len(&self) -> usize {
self.inner.len() + self.last.len()
}
}
impl<'a, T, P> Clone for Pairs<'a, T, P> {
fn clone(&self) -> Self {
Pairs {
inner: self.inner.clone(),
last: self.last.clone(),
}
}
}
pub struct PairsMut<'a, T: 'a, P: 'a> {
inner: slice::IterMut<'a, (T, P)>,
last: option::IntoIter<&'a mut T>,
}
impl<'a, T, P> Iterator for PairsMut<'a, T, P> {
type Item = Pair<&'a mut T, &'a mut P>;
fn next(&mut self) -> Option<Self::Item> {
self.inner
.next()
.map(|(t, p)| Pair::Punctuated(t, p))
.or_else(|| self.last.next().map(Pair::End))
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<'a, T, P> DoubleEndedIterator for PairsMut<'a, T, P> {
fn next_back(&mut self) -> Option<Self::Item> {
self.last
.next()
.map(Pair::End)
.or_else(|| self.inner.next_back().map(|(t, p)| Pair::Punctuated(t, p)))
}
}
impl<'a, T, P> ExactSizeIterator for PairsMut<'a, T, P> {
fn len(&self) -> usize {
self.inner.len() + self.last.len()
}
}
pub struct IntoPairs<T, P> {
inner: vec::IntoIter<(T, P)>,
last: option::IntoIter<T>,
}
impl<T, P> Iterator for IntoPairs<T, P> {
type Item = Pair<T, P>;
fn next(&mut self) -> Option<Self::Item> {
self.inner
.next()
.map(|(t, p)| Pair::Punctuated(t, p))
.or_else(|| self.last.next().map(Pair::End))
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<T, P> DoubleEndedIterator for IntoPairs<T, P> {
fn next_back(&mut self) -> Option<Self::Item> {
self.last
.next()
.map(Pair::End)
.or_else(|| self.inner.next_back().map(|(t, p)| Pair::Punctuated(t, p)))
}
}
impl<T, P> ExactSizeIterator for IntoPairs<T, P> {
fn len(&self) -> usize {
self.inner.len() + self.last.len()
}
}
impl<T, P> Clone for IntoPairs<T, P>
where
T: Clone,
P: Clone,
{
fn clone(&self) -> Self {
IntoPairs {
inner: self.inner.clone(),
last: self.last.clone(),
}
}
}
pub struct IntoIter<T> {
inner: vec::IntoIter<T>,
}
impl<T> Iterator for IntoIter<T> {
type Item = T;
fn next(&mut self) -> Option<Self::Item> {
self.inner.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<T> DoubleEndedIterator for IntoIter<T> {
fn next_back(&mut self) -> Option<Self::Item> {
self.inner.next_back()
}
}
impl<T> ExactSizeIterator for IntoIter<T> {
fn len(&self) -> usize {
self.inner.len()
}
}
impl<T> Clone for IntoIter<T>
where
T: Clone,
{
fn clone(&self) -> Self {
IntoIter {
inner: self.inner.clone(),
}
}
}
pub struct Iter<'a, T: 'a> {
inner: Box<dyn IterTrait<'a, T, Item = &'a T> + 'a>,
}
trait IterTrait<'a, T: 'a>:
DoubleEndedIterator<Item = &'a T> + ExactSizeIterator<Item = &'a T>
{
fn clone_box(&self) -> Box<dyn IterTrait<'a, T, Item = &'a T> + 'a>;
}
struct PrivateIter<'a, T: 'a, P: 'a> {
inner: slice::Iter<'a, (T, P)>,
last: option::IntoIter<&'a T>,
}
#[cfg(any(feature = "full", feature = "derive"))]
pub(crate) fn empty_punctuated_iter<'a, T>() -> Iter<'a, T> {
Iter {
inner: Box::new(iter::empty()),
}
}
impl<'a, T> Clone for Iter<'a, T> {
fn clone(&self) -> Self {
Iter {
inner: self.inner.clone_box(),
}
}
}
impl<'a, T> Iterator for Iter<'a, T> {
type Item = &'a T;
fn next(&mut self) -> Option<Self::Item> {
self.inner.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
fn next_back(&mut self) -> Option<Self::Item> {
self.inner.next_back()
}
}
impl<'a, T> ExactSizeIterator for Iter<'a, T> {
fn len(&self) -> usize {
self.inner.len()
}
}
impl<'a, T, P> Iterator for PrivateIter<'a, T, P> {
type Item = &'a T;
fn next(&mut self) -> Option<Self::Item> {
self.inner
.next()
.map(|pair| &pair.0)
.or_else(|| self.last.next())
}
}
impl<'a, T, P> DoubleEndedIterator for PrivateIter<'a, T, P> {
fn next_back(&mut self) -> Option<Self::Item> {
self.last
.next()
.or_else(|| self.inner.next_back().map(|pair| &pair.0))
}
}
impl<'a, T, P> ExactSizeIterator for PrivateIter<'a, T, P> {
fn len(&self) -> usize {
self.inner.len() + self.last.len()
}
}
impl<'a, T, P> Clone for PrivateIter<'a, T, P> {
fn clone(&self) -> Self {
PrivateIter {
inner: self.inner.clone(),
last: self.last.clone(),
}
}
}
impl<'a, T: 'a, I: 'a> IterTrait<'a, T> for I
where
I: DoubleEndedIterator<Item = &'a T> + ExactSizeIterator<Item = &'a T> + Clone,
{
fn clone_box(&self) -> Box<dyn IterTrait<'a, T, Item = &'a T> + 'a> {
Box::new(self.clone())
}
}
pub struct IterMut<'a, T: 'a> {
inner: Box<dyn IterMutTrait<'a, T, Item = &'a mut T> + 'a>,
}
trait IterMutTrait<'a, T: 'a>:
DoubleEndedIterator<Item = &'a mut T> + ExactSizeIterator<Item = &'a mut T>
{
}
struct PrivateIterMut<'a, T: 'a, P: 'a> {
inner: slice::IterMut<'a, (T, P)>,
last: option::IntoIter<&'a mut T>,
}
#[cfg(any(feature = "full", feature = "derive"))]
pub(crate) fn empty_punctuated_iter_mut<'a, T>() -> IterMut<'a, T> {
IterMut {
inner: Box::new(iter::empty()),
}
}
impl<'a, T> Iterator for IterMut<'a, T> {
type Item = &'a mut T;
fn next(&mut self) -> Option<Self::Item> {
self.inner.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.len(), Some(self.len()))
}
}
impl<'a, T> DoubleEndedIterator for IterMut<'a, T> {
fn next_back(&mut self) -> Option<Self::Item> {
self.inner.next_back()
}
}
impl<'a, T> ExactSizeIterator for IterMut<'a, T> {
fn len(&self) -> usize {
self.inner.len()
}
}
impl<'a, T, P> Iterator for PrivateIterMut<'a, T, P> {
type Item = &'a mut T;
fn next(&mut self) -> Option<Self::Item> {
self.inner
.next()
.map(|pair| &mut pair.0)
.or_else(|| self.last.next())
}
}
impl<'a, T, P> DoubleEndedIterator for PrivateIterMut<'a, T, P> {
fn next_back(&mut self) -> Option<Self::Item> {
self.last
.next()
.or_else(|| self.inner.next_back().map(|pair| &mut pair.0))
}
}
impl<'a, T, P> ExactSizeIterator for PrivateIterMut<'a, T, P> {
fn len(&self) -> usize {
self.inner.len() + self.last.len()
}
}
impl<'a, T: 'a, I: 'a> IterMutTrait<'a, T> for I where
I: DoubleEndedIterator<Item = &'a mut T> + ExactSizeIterator<Item = &'a mut T>
{
}
pub enum Pair<T, P> {
Punctuated(T, P),
End(T),
}
impl<T, P> Pair<T, P> {
pub fn into_value(self) -> T {
match self {
Pair::Punctuated(t, _) | Pair::End(t) => t,
}
}
pub fn value(&self) -> &T {
match self {
Pair::Punctuated(t, _) | Pair::End(t) => t,
}
}
pub fn value_mut(&mut self) -> &mut T {
match self {
Pair::Punctuated(t, _) | Pair::End(t) => t,
}
}
pub fn punct(&self) -> Option<&P> {
match self {
Pair::Punctuated(_, d) => Some(d),
Pair::End(_) => None,
}
}
pub fn new(t: T, d: Option<P>) -> Self {
match d {
Some(d) => Pair::Punctuated(t, d),
None => Pair::End(t),
}
}
pub fn into_tuple(self) -> (T, Option<P>) {
match self {
Pair::Punctuated(t, d) => (t, Some(d)),
Pair::End(t) => (t, None),
}
}
}
#[cfg(feature = "clone-impls")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))]
impl<T, P> Clone for Pair<T, P>
where
T: Clone,
P: Clone,
{
fn clone(&self) -> Self {
match self {
Pair::Punctuated(t, p) => Pair::Punctuated(t.clone(), p.clone()),
Pair::End(t) => Pair::End(t.clone()),
}
}
}
impl<T, P> Index<usize> for Punctuated<T, P> {
type Output = T;
fn index(&self, index: usize) -> &Self::Output {
if index == self.len() - 1 {
match &self.last {
Some(t) => t,
None => &self.inner[index].0,
}
} else {
&self.inner[index].0
}
}
}
impl<T, P> IndexMut<usize> for Punctuated<T, P> {
fn index_mut(&mut self, index: usize) -> &mut Self::Output {
if index == self.len() - 1 {
match &mut self.last {
Some(t) => t,
None => &mut self.inner[index].0,
}
} else {
&mut self.inner[index].0
}
}
}
#[cfg(feature = "printing")]
mod printing {
use super::*;
use proc_macro2::TokenStream;
use quote::{ToTokens, TokenStreamExt};
#[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
impl<T, P> ToTokens for Punctuated<T, P>
where
T: ToTokens,
P: ToTokens,
{
fn to_tokens(&self, tokens: &mut TokenStream) {
tokens.append_all(self.pairs())
}
}
#[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
impl<T, P> ToTokens for Pair<T, P>
where
T: ToTokens,
P: ToTokens,
{
fn to_tokens(&self, tokens: &mut TokenStream) {
match self {
Pair::Punctuated(a, b) => {
a.to_tokens(tokens);
b.to_tokens(tokens);
}
Pair::End(a) => a.to_tokens(tokens),
}
}
}
}