Group in proc_macro - Rust
Description: A delimited token stream.

## Group

# Struct Group

1.29.0 · Source

    pub struct Group(/* private fields */);

Expand description

A delimited token stream.

A `Group` internally contains a `TokenStream` which is surrounded by `Delimiter`s.

## Implementations§

Source§

### impl Group

1.29.0 · Source

#### 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.

1.29.0 · Source

#### pub fn delimiter(&self) -> Delimiter

Returns the delimiter of this `Group`

1.29.0 · Source

#### 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.

1.29.0 · Source

#### pub fn span(&self) -> Span

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

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

1.55.0 · Source

#### pub fn span_open(&self) -> Span

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

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

1.55.0 · Source

#### pub fn span_close(&self) -> Span

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

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

1.29.0 · Source

#### 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§

1.29.0 · Source§

### impl Clone for Group

Source§

#### fn clone(&self) -> Group

Returns a duplicate of the value. Read more
1.0.0 · Source§

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

Performs copy-assignment from `source`. Read more
1.29.0 · Source§

### impl Debug for Group

Source§

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

Formats the value using the given formatter. Read more
1.29.0 · Source§

### 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::Group`s with `Delimiter::None` delimiters.

Source§

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

Formats the value using the given formatter. Read more
1.92.0 · Source§

### impl Extend<Group> for TokenStream

Source§

#### fn extend<T: IntoIterator<Item = Group>>(&mut self, iter: T)

Extends a collection with the contents of an iterator. Read more
Source§

#### fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (`extend_one` #72631)
Extends a collection with exactly one element.
Source§

#### fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (`extend_one` #72631)
Reserves capacity in a collection for the given number of additional elements. Read more
1.29.0 · Source§

### impl From<Group> for TokenTree

Source§

#### fn from(g: Group) -> TokenTree

Converts to this type from the input type.
Source§

### impl ToTokens for Group

Source§

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

🔬This is a nightly-only experimental API. (`proc_macro_totokens` #130977)
Write `self` to the given `TokenStream`. Read more
Source§

#### fn to_token_stream(&self) -> TokenStream

🔬This is a nightly-only experimental API. (`proc_macro_totokens` #130977)
Convert `self` directly into a `TokenStream` object. Read more
Source§

#### fn into_token_stream(self) -> TokenStream
where Self: Sized,

🔬This is a nightly-only experimental API. (`proc_macro_totokens` #130977)
Convert `self` directly into a `TokenStream` object. Read more
1.29.0 · Source§

### impl !Send for Group

1.29.0 · Source§

### impl !Sync for Group

## Auto Trait Implementations§

§

### impl Freeze for Group

§

### impl RefUnwindSafe for Group

§

### impl Unpin for Group

§

### impl UnwindSafe for Group

## Blanket Implementations§

Source§

### impl<T> Any for T
where T: 'static + ?Sized,

Source§

#### fn type_id(&self) -> TypeId

Gets the `TypeId` of `self`. Read more
Source§

### impl<T> Borrow<T> for T
where T: ?Sized,

Source§

#### fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

### impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

#### fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
Source§

### impl<T> CloneToUninit for T
where T: Clone,

Source§

#### unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (`clone_to_uninit` #126799)
Performs copy-assignment from `self` to `dest`. Read more
Source§

### impl<T> From<T> for T

Source§

#### fn from(t: T) -> T

Returns the argument unchanged.

Source§

### impl<T, U> Into<U> for T
where U: From<T>,

Source§

#### fn into(self) -> U

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

Source§

### impl<T> ToOwned for T
where T: Clone,

Source§

#### type Owned = T

The resulting type after obtaining ownership.
Source§

#### fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
Source§

#### fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
Source§

### impl<T> ToString for T
where T: Display + ?Sized,

Source§

#### fn to_string(&self) -> String

Converts the given value to a `String`. Read more
Source§

### impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

#### type Error = Infallible

The type returned in the event of a conversion error.
Source§

#### fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

### impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

#### type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
Source§

#### fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.