Struct proc_macro::Group

pub struct Group { /* fields omitted */ }

🔬 This is a nightly-only experimental API. (proc_macro #38356)

A delimited token stream.

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

Methods

impl Group

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

🔬 This is a nightly-only experimental API. (proc_macro #38356)

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

🔬 This is a nightly-only experimental API. (proc_macro #38356)

Returns the delimiter of this Group

pub fn stream(&self) -> TokenStream

🔬 This is a nightly-only experimental API. (proc_macro #38356)

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

🔬 This is a nightly-only experimental API. (proc_macro #38356)

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

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

🔬 This is a nightly-only experimental API. (proc_macro #38356)

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 From<Group> for TokenTree

fn from(g: Group) -> TokenTree

Performs the conversion.

impl Clone for Group

fn clone(&self) -> Group

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Group

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl !Send for Group

impl !Sync for Group

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, f: &mut Formatter) -> Result

Formats the value using the given formatter.