Struct Group 

pub struct Group { /* private fields */ }

A delimited token stream.

A Group internally contains a TokenStream which is surrounded by Delimiters.

Implementations

impl Group

pub fn new(delimiter: Delimiter, stream: TokenStream) -> Group

Creates a new Group with the given delimiter and token stream.

This constructor will set the span for this group to Span::call_site(). To change the span you can use the set_span method below.

pub fn delimiter(&self) -> Delimiter

Returns the punctuation used as the delimiter for this group: a set of parentheses, square brackets, or curly braces.

pub fn stream(&self) -> TokenStream

Returns the TokenStream of tokens that are delimited in this Group.

Note that the returned token stream does not include the delimiter returned above.

pub fn span(&self) -> Span

Returns the span for the delimiters of this token stream, spanning the entire Group.

pub fn span(&self) -> Span {
           ^^^^^^^

pub fn span_open(&self) -> Span

Returns the span pointing to the opening delimiter of this group.

pub fn span_open(&self) -> Span {
                ^

pub fn span_close(&self) -> Span

Returns the span pointing to the closing delimiter of this group.

pub fn span_close(&self) -> Span {
                       ^

pub fn delim_span(&self) -> DelimSpan

Returns an object that holds this group’s span_open() and span_close() together (in a more compact representation than holding those 2 spans individually).

pub fn set_span(&mut self, span: Span)

Configures the span for this Group’s delimiters, but not its internal tokens.

This method will not set the span of all the internal tokens spanned by this group, but rather it will only set the span of the delimiter tokens at the level of the Group.

Trait Implementations

impl Clone for Group

fn clone(&self) -> Group

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Group

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for Group

Prints the group as a string that should be losslessly convertible back into the same group (modulo spans), except for possibly TokenTree::Groups with Delimiter::None delimiters.

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<BraceGroup> for Group

fn from(group: BraceGroup) -> Group

Converts to this type from the input type.

impl From<BracketGroup> for Group

fn from(group: BracketGroup) -> Group

Converts to this type from the input type.

impl From<Group> for TokenTree

fn from(g: Group) -> TokenTree

Converts to this type from the input type.

impl From<NoneGroup> for Group

fn from(group: NoneGroup) -> Group

Converts to this type from the input type.

impl From<ParenthesisGroup> for Group

fn from(group: ParenthesisGroup) -> Group

Converts to this type from the input type.

impl Parser for Group

fn parser( tokens: &mut ShadowCountedIter<'_, <TokenStream as IntoIterator>::IntoIter>, ) -> Result<Group, Error>

The actual parsing function that must be implemented. This mutates the tokens iterator directly. It should not be called from user code except for implementing parsers itself and then only when the rules below are followed.

impl ToTokens for Group

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

Write &self to the given TokenStream.

fn to_token_iter( &self, ) -> ShadowCountedIter<'_, <TokenStream as IntoIterator>::IntoIter>

Convert &self into a TokenIter object.

fn into_token_iter<'a>( self, ) -> ShadowCountedIter<'a, <TokenStream as IntoIterator>::IntoIter>

where Self: Sized,

Convert self into a TokenIter object.

fn to_token_stream(&self) -> TokenStream

Convert &self into a TokenStream object.

fn into_token_stream(self) -> TokenStream

where Self: Sized,

Convert self into a TokenStream object.

fn tokens_to_string(&self) -> String

Convert &self into a String object. This is mostly used in the test suite to compare the outputs. When the input is a &str then this parses it and returns a normalized String.