Struct syntax::ext::base::DummyResult

pub struct DummyResult { /* fields omitted */ }

Fill-in macro expansion result, to allow compilation to continue after hitting errors.

Methods

impl DummyResult

pub fn any(span: Span) -> Box<dyn MacResult + 'static>

Creates a default MacResult that can be anything.

Use this as a return value after hitting any errors and calling span_err.

pub fn any_valid(span: Span) -> Box<dyn MacResult + 'static>

Same as any, but must be a valid fragment, not error.

pub fn expr(span: Span) -> Box<dyn MacResult + 'static>

Creates a default MacResult that can only be an expression.

Use this for macros that must expand to an expression, so even if an error is encountered internally, the user will receive an error that they also used it in the wrong place.

pub fn raw_expr(sp: Span, is_error: bool) -> P<Expr>

A plain dummy expression.

pub fn raw_pat(sp: Span) -> Pat

A plain dummy pattern.

pub fn raw_ty(sp: Span, is_error: bool) -> P<Ty>

A plain dummy type.

Trait Implementations

impl MacResult for DummyResult

fn make_expr(self: Box<DummyResult>) -> Option<P<Expr>>

Creates an expression.

fn make_pat(self: Box<DummyResult>) -> Option<P<Pat>>

Creates a pattern.

fn make_items(self: Box<DummyResult>) -> Option<SmallVec<[P<Item>; 1]>>

Creates zero or more items.

fn make_impl_items(self: Box<DummyResult>) -> Option<SmallVec<[ImplItem; 1]>>

Creates zero or more impl items.

fn make_trait_items(self: Box<DummyResult>) -> Option<SmallVec<[TraitItem; 1]>>

Creates zero or more trait items.

fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ForeignItem; 1]>>

Creates zero or more items in an extern {} block

fn make_stmts(self: Box<DummyResult>) -> Option<SmallVec<[Stmt; 1]>>

Creates zero or more statements.

fn make_ty(self: Box<DummyResult>) -> Option<P<Ty>>

impl Copy for DummyResult

impl Clone for DummyResult

fn clone(&self) -> DummyResult

Returns a copy of the value.

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

Performs copy-assignment from source.