Struct syn::punctuated::Punctuated

pub struct Punctuated<T, P> { /* private fields */ }

A punctuated sequence of syntax tree nodes of type T separated by punctuation of type P.

Refer to the module documentation for details about punctuated sequences.

Implementations

impl<T, P> Punctuated<T, P>

pub const fn new() -> Self

Creates an empty punctuated sequence.

pub fn is_empty(&self) -> bool

Determines whether this punctuated sequence is empty, meaning it contains no syntax tree nodes or punctuation.

pub fn len(&self) -> usize

Returns the number of syntax tree nodes in this punctuated sequence.

This is the number of nodes of type T, not counting the punctuation of type P.

pub fn first(&self) -> Option<&T>

Borrows the first element in this sequence.

pub fn first_mut(&mut self) -> Option<&mut T>

Mutably borrows the first element in this sequence.

pub fn last(&self) -> Option<&T>

Borrows the last element in this sequence.

pub fn last_mut(&mut self) -> Option<&mut T>

Mutably borrows the last element in this sequence.

pub fn iter(&self) -> Iter<'_, T>

Returns an iterator over borrowed syntax tree nodes of type &T.

pub fn iter_mut(&mut self) -> IterMut<'_, T>

Returns an iterator over mutably borrowed syntax tree nodes of type &mut T.

pub fn pairs(&self) -> Pairs<'_, T, P>

Returns an iterator over the contents of this sequence as borrowed punctuated pairs.

pub fn pairs_mut(&mut self) -> PairsMut<'_, T, P>

Returns an iterator over the contents of this sequence as mutably borrowed punctuated pairs.

pub fn into_pairs(self) -> IntoPairs<T, P>

Returns an iterator over the contents of this sequence as owned punctuated pairs.

pub fn push_value(&mut self, value: T)

Appends a syntax tree node onto the end of this punctuated sequence. The sequence must already have a trailing punctuation, or be empty.

Use push instead if the punctuated sequence may or may not already have trailing punctuation.

Panics

Panics if the sequence is nonempty and does not already have a trailing punctuation.

pub fn push_punct(&mut self, punctuation: P)

Appends a trailing punctuation onto the end of this punctuated sequence. The sequence must be non-empty and must not already have trailing punctuation.

Panics

Panics if the sequence is empty or already has a trailing punctuation.

pub fn pop(&mut self) -> Option<Pair<T, P>>

Removes the last punctuated pair from this sequence, or None if the sequence is empty.

pub fn trailing_punct(&self) -> bool

Determines whether this punctuated sequence ends with a trailing punctuation.

pub fn empty_or_trailing(&self) -> bool

Returns true if either this Punctuated is empty, or it has a trailing punctuation.

Equivalent to punctuated.is_empty() || punctuated.trailing_punct().

pub fn push(&mut self, value: T)where
    P: Default,

Appends a syntax tree node onto the end of this punctuated sequence.

If there is not a trailing punctuation in this sequence when this method is called, the default value of punctuation type P is inserted before the given value of type T.

pub fn insert(&mut self, index: usize, value: T)where
    P: Default,

Inserts an element at position index.

Panics

Panics if index is greater than the number of elements previously in this punctuated sequence.

pub fn clear(&mut self)

Clears the sequence of all values and punctuation, making it empty.

pub fn parse_terminated(input: ParseStream<'_>) -> Result<Self>where
    T: Parse,
    P: Parse,

Parses zero or more occurrences of T separated by punctuation of type P, with optional trailing punctuation.

Parsing continues until the end of this parse stream. The entire content of this parse stream must consist of T and P.

pub fn parse_terminated_with(
    input: ParseStream<'_>,
    parser: fn(_: ParseStream<'_>) -> Result<T>
) -> Result<Self>where
    P: Parse,

Parses zero or more occurrences of T using the given parse function, separated by punctuation of type P, with optional trailing punctuation.

Like parse_terminated, the entire content of this stream is expected to be parsed.

pub fn parse_separated_nonempty(input: ParseStream<'_>) -> Result<Self>where
    T: Parse,
    P: Token + Parse,

Parses one or more occurrences of T separated by punctuation of type P, not accepting trailing punctuation.

Parsing continues as long as punctuation P is present at the head of the stream. This method returns upon parsing a T and observing that it is not followed by a P, even if there are remaining tokens in the stream.

pub fn parse_separated_nonempty_with(
    input: ParseStream<'_>,
    parser: fn(_: ParseStream<'_>) -> Result<T>
) -> Result<Self>where
    P: Token + Parse,

Parses one or more occurrences of T using the given parse function, separated by punctuation of type P, not accepting trailing punctuation.

Like parse_separated_nonempty, may complete early without parsing the entire content of this stream.

Trait Implementations

impl<T, P> Clone for Punctuated<T, P>where
    T: Clone,
    P: Clone,

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T, P> Default for Punctuated<T, P>

fn default() -> Self

Returns the “default value” for a type.

impl<T, P> Extend<Pair<T, P>> for Punctuated<T, P>where
    P: Default,

fn extend<I: IntoIterator<Item = Pair<T, P>>>(&mut self, i: I)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<T, P> Extend<T> for Punctuated<T, P>where
    P: Default,

fn extend<I: IntoIterator<Item = T>>(&mut self, i: I)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<T, P> FromIterator<Pair<T, P>> for Punctuated<T, P>

fn from_iter<I: IntoIterator<Item = Pair<T, P>>>(i: I) -> Self

Creates a value from an iterator.

impl<T, P> FromIterator<T> for Punctuated<T, P>where
    P: Default,

fn from_iter<I: IntoIterator<Item = T>>(i: I) -> Self

Creates a value from an iterator.

impl<T, P> Index<usize> for Punctuated<T, P>

type Output = T

The returned type after indexing.

fn index(&self, index: usize) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<T, P> IndexMut<usize> for Punctuated<T, P>

fn index_mut(&mut self, index: usize) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl<'a, T, P> IntoIterator for &'a Punctuated<T, P>

type Item = &'a T

The type of the elements being iterated over.

type IntoIter = Iter<'a, T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'a, T, P> IntoIterator for &'a mut Punctuated<T, P>

type Item = &'a mut T

The type of the elements being iterated over.

type IntoIter = IterMut<'a, T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<T, P> IntoIterator for Punctuated<T, P>

type Item = T

The type of the elements being iterated over.

type IntoIter = IntoIter<T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<T, P> ToTokens for Punctuated<T, P>where
    T: ToTokens,
    P: ToTokens,

fn to_tokens(&self, tokens: &mut TokenStream)

Write self to the given TokenStream.

fn to_token_stream(&self) -> TokenStream

Convert self directly into a TokenStream object.

fn into_token_stream(self) -> TokenStreamwhere
    Self: Sized,

Convert self directly into a TokenStream object.