Struct CondChecker

struct CondChecker<'a> {
    parser: &'a Parser<'a>,
    forbid_let_reason: Option<ForbiddenLetReason>,
    missing_let: Option<MaybeMissingLet>,
    comparison: Option<MaybeComparison>,
}

Visitor to check for invalid/unstable use of ExprKind::Let that can’t easily be caught in parsing. For example:

// Only know that the let isn't allowed once the `||` token is reached
if let Some(x) = y || true {}
// Only know that the let isn't allowed once the second `=` token is reached.
if let Some(x) = y && z = 1 {}

Fields

parser: &'a Parser<'a>

forbid_let_reason: Option<ForbiddenLetReason>

missing_let: Option<MaybeMissingLet>

comparison: Option<MaybeComparison>

Implementations

impl<'a> CondChecker<'a>

fn new(parser: &'a Parser<'a>) -> Self

Trait Implementations

impl MutVisitor for CondChecker<'_>

fn visit_expr(&mut self, e: &mut P<Expr>)

const VISIT_TOKENS: bool = false

Mutable token visiting only exists for the macro_rules token marker and should not be used otherwise. Token visitor would be entirely separate from the regular visitor if the marker didn’t have to visit AST fragments in nonterminal tokens.

fn visit_crate(&mut self, c: &mut Crate)

fn visit_meta_list_item(&mut self, list_item: &mut MetaItemInner)

fn visit_meta_item(&mut self, meta_item: &mut MetaItem)

fn visit_use_tree(&mut self, use_tree: &mut UseTree)

fn visit_foreign_item(&mut self, ni: &mut P<Item<ForeignItemKind>>)

fn flat_map_foreign_item( &mut self, ni: P<Item<ForeignItemKind>>, ) -> SmallVec<[P<Item<ForeignItemKind>>; 1]>

fn visit_item(&mut self, i: &mut P<Item>)

fn flat_map_item(&mut self, i: P<Item>) -> SmallVec<[P<Item>; 1]>

fn visit_fn_header(&mut self, header: &mut FnHeader)

fn visit_field_def(&mut self, fd: &mut FieldDef)

fn flat_map_field_def(&mut self, fd: FieldDef) -> SmallVec<[FieldDef; 1]>

fn visit_assoc_item(&mut self, i: &mut P<Item<AssocItemKind>>, ctxt: AssocCtxt)

fn flat_map_assoc_item( &mut self, i: P<Item<AssocItemKind>>, ctxt: AssocCtxt, ) -> SmallVec<[P<Item<AssocItemKind>>; 1]>

fn visit_fn_decl(&mut self, d: &mut P<FnDecl>)

fn visit_fn(&mut self, fk: FnKind<'_>, _: Span, _: NodeId)

Span and NodeId are mutated at the caller site.

fn visit_coroutine_kind(&mut self, a: &mut CoroutineKind)

fn visit_closure_binder(&mut self, b: &mut ClosureBinder)

fn visit_block(&mut self, b: &mut P<Block>)

fn flat_map_stmt(&mut self, s: Stmt) -> SmallVec<[Stmt; 1]>

fn visit_arm(&mut self, arm: &mut Arm)

fn flat_map_arm(&mut self, arm: Arm) -> SmallVec<[Arm; 1]>

fn visit_pat(&mut self, p: &mut P<Pat>)

fn visit_anon_const(&mut self, c: &mut AnonConst)

fn visit_method_receiver_expr(&mut self, ex: &mut P<Expr>)

This method is a hack to workaround unstable of stmt_expr_attributes. It can be removed once that feature is stabilized.

fn filter_map_expr(&mut self, e: P<Expr>) -> Option<P<Expr>>

fn visit_generic_arg(&mut self, arg: &mut GenericArg)

fn visit_ty(&mut self, t: &mut P<Ty>)

fn visit_lifetime(&mut self, l: &mut Lifetime)

fn visit_assoc_item_constraint(&mut self, c: &mut AssocItemConstraint)

fn visit_foreign_mod(&mut self, nm: &mut ForeignMod)

fn visit_variant(&mut self, v: &mut Variant)

fn flat_map_variant(&mut self, v: Variant) -> SmallVec<[Variant; 1]>

fn visit_ident(&mut self, i: &mut Ident)

fn visit_path(&mut self, p: &mut Path)

fn visit_path_segment(&mut self, p: &mut PathSegment)

fn visit_qself(&mut self, qs: &mut Option<P<QSelf>>)

fn visit_generic_args(&mut self, p: &mut GenericArgs)

fn visit_angle_bracketed_parameter_data(&mut self, p: &mut AngleBracketedArgs)

fn visit_parenthesized_parameter_data(&mut self, p: &mut ParenthesizedArgs)

fn visit_local(&mut self, l: &mut P<Local>)

fn visit_mac_call(&mut self, mac: &mut MacCall)

fn visit_macro_def(&mut self, def: &mut MacroDef)

fn visit_label(&mut self, label: &mut Label)

fn visit_attribute(&mut self, at: &mut Attribute)

fn visit_param(&mut self, param: &mut Param)

fn flat_map_param(&mut self, param: Param) -> SmallVec<[Param; 1]>

fn visit_generics(&mut self, generics: &mut Generics)

fn visit_trait_ref(&mut self, tr: &mut TraitRef)

fn visit_poly_trait_ref(&mut self, p: &mut PolyTraitRef)

fn visit_variant_data(&mut self, vdata: &mut VariantData)

fn visit_generic_param(&mut self, param: &mut GenericParam)

fn flat_map_generic_param( &mut self, param: GenericParam, ) -> SmallVec<[GenericParam; 1]>

fn visit_param_bound(&mut self, tpb: &mut GenericBound, _ctxt: BoundKind)

fn visit_precise_capturing_arg(&mut self, arg: &mut PreciseCapturingArg)

fn visit_mt(&mut self, mt: &mut MutTy)

fn visit_expr_field(&mut self, f: &mut ExprField)

fn flat_map_expr_field(&mut self, f: ExprField) -> SmallVec<[ExprField; 1]>

fn visit_where_clause(&mut self, where_clause: &mut WhereClause)

fn visit_where_predicate(&mut self, where_predicate: &mut WherePredicate)

fn visit_vis(&mut self, vis: &mut Visibility)

fn visit_id(&mut self, _id: &mut NodeId)

fn visit_span(&mut self, _sp: &mut Span)

fn visit_pat_field(&mut self, fp: &mut PatField)

fn flat_map_pat_field(&mut self, fp: PatField) -> SmallVec<[PatField; 1]>

fn visit_inline_asm(&mut self, asm: &mut InlineAsm)

fn visit_inline_asm_sym(&mut self, sym: &mut InlineAsmSym)

fn visit_format_args(&mut self, fmt: &mut FormatArgs)

fn visit_capture_by(&mut self, capture_by: &mut CaptureBy)

fn visit_fn_ret_ty(&mut self, fn_ret_ty: &mut FnRetTy)

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 48 bytes