Struct syntax::ext::hygiene::ExpnData

pub struct ExpnData {
    pub kind: ExpnKind,
    pub parent: ExpnId,
    pub call_site: Span,
    pub def_site: Span,
    pub allow_internal_unstable: Option<Rc<[Symbol]>>,
    pub allow_internal_unsafe: bool,
    pub local_inner_macros: bool,
    pub edition: Edition,
}

A subset of properties from both macro definition and macro call available through global data. Avoid using this if you have access to the original definition or call structures.

Fields

kind: ExpnKind

The kind of this expansion - macro or compiler desugaring.

parent: ExpnId

The expansion that produced this expansion.

call_site: Span

The location of the actual macro invocation or syntax sugar , e.g. let x = foo!(); or if let Some(y) = x {}

This may recursively refer to other macro invocations, e.g., if foo!() invoked bar!() internally, and there was an expression inside bar!; the call_site of the expression in the expansion would point to the bar! invocation; that call_site span would have its own ExpnData, with the call_site pointing to the foo! invocation.

def_site: Span

The span of the macro definition (possibly dummy). This span serves only informational purpose and is not used for resolution.

allow_internal_unstable: Option<Rc<[Symbol]>>

List of #[unstable]/feature-gated features that the macro is allowed to use internally without forcing the whole crate to opt-in to them.

allow_internal_unsafe: bool

Whether the macro is allowed to use unsafe internally even if the user crate has #![forbid(unsafe_code)].

local_inner_macros: bool

Enables the macro helper hack (ident!(...) -> $crate::ident!(...)) for a given macro.

edition: Edition

Edition of the crate in which the macro is defined.

Methods

impl ExpnData

pub fn default(kind: ExpnKind, call_site: Span, edition: Edition) -> ExpnData

Constructs expansion data with default properties.

pub fn allow_unstable(
    kind: ExpnKind,
    call_site: Span,
    edition: Edition,
    allow_internal_unstable: Rc<[Symbol]>
) -> ExpnData

pub fn is_root(&self) -> bool

Trait Implementations

impl Decodable for ExpnData

fn decode<__D>(d: &mut __D) -> Result<ExpnData, <__D as Decoder>::Error> where
    __D: Decoder, 

impl Debug for ExpnData

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

Formats the value using the given formatter.

impl Clone for ExpnData

fn clone(&self) -> ExpnData

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Encodable for ExpnData

fn encode<__S>(&self, s: &mut __S) -> Result<(), <__S as Encoder>::Error> where
    __S: Encoder,