Enum rustc_middle::thir::ExprKind

pub enum ExprKind<'tcx> {
    Scope {
        region_scope: Scope,
        lint_level: LintLevel,
        value: ExprId,
    },
    Box {
        value: ExprId,
    },
    If {
        if_then_scope: Scope,
        cond: ExprId,
        then: ExprId,
        else_opt: Option<ExprId>,
    },
    Call {
        ty: Ty<'tcx>,
        fun: ExprId,
        args: Box<[ExprId]>,
        from_hir_call: bool,
        fn_span: Span,
    },
    Deref {
        arg: ExprId,
    },
    Binary {
        op: BinOp,
        lhs: ExprId,
        rhs: ExprId,
    },
    LogicalOp {
        op: LogicalOp,
        lhs: ExprId,
        rhs: ExprId,
    },
    Unary {
        op: UnOp,
        arg: ExprId,
    },
    Cast {
        source: ExprId,
    },
    Use {
        source: ExprId,
    },
    NeverToAny {
        source: ExprId,
    },
    PointerCoercion {
        cast: PointerCoercion,
        source: ExprId,
    },
    Loop {
        body: ExprId,
    },
    Let {
        expr: ExprId,
        pat: Box<Pat<'tcx>>,
    },
    Match {
        scrutinee: ExprId,
        scrutinee_hir_id: HirId,
        arms: Box<[ArmId]>,
    },
    Block {
        block: BlockId,
    },
    Assign {
        lhs: ExprId,
        rhs: ExprId,
    },
    AssignOp {
        op: BinOp,
        lhs: ExprId,
        rhs: ExprId,
    },
    Field {
        lhs: ExprId,
        variant_index: VariantIdx,
        name: FieldIdx,
    },
    Index {
        lhs: ExprId,
        index: ExprId,
    },
    VarRef {
        id: LocalVarId,
    },
    UpvarRef {
        closure_def_id: DefId,
        var_hir_id: LocalVarId,
    },
    Borrow {
        borrow_kind: BorrowKind,
        arg: ExprId,
    },
    AddressOf {
        mutability: Mutability,
        arg: ExprId,
    },
    Break {
        label: Scope,
        value: Option<ExprId>,
    },
    Continue {
        label: Scope,
    },
    Return {
        value: Option<ExprId>,
    },
    Become {
        value: ExprId,
    },
    ConstBlock {
        did: DefId,
        args: GenericArgsRef<'tcx>,
    },
    Repeat {
        value: ExprId,
        count: Const<'tcx>,
    },
    Array {
        fields: Box<[ExprId]>,
    },
    Tuple {
        fields: Box<[ExprId]>,
    },
    Adt(Box<AdtExpr<'tcx>>),
    PlaceTypeAscription {
        source: ExprId,
        user_ty: Option<Box<CanonicalUserType<'tcx>>>,
    },
    ValueTypeAscription {
        source: ExprId,
        user_ty: Option<Box<CanonicalUserType<'tcx>>>,
    },
    Closure(Box<ClosureExpr<'tcx>>),
    Literal {
        lit: &'tcx Lit,
        neg: bool,
    },
    NonHirLiteral {
        lit: ScalarInt,
        user_ty: Option<Box<CanonicalUserType<'tcx>>>,
    },
    ZstLiteral {
        user_ty: Option<Box<CanonicalUserType<'tcx>>>,
    },
    NamedConst {
        def_id: DefId,
        args: GenericArgsRef<'tcx>,
        user_ty: Option<Box<CanonicalUserType<'tcx>>>,
    },
    ConstParam {
        param: ParamConst,
        def_id: DefId,
    },
    StaticRef {
        alloc_id: AllocId,
        ty: Ty<'tcx>,
        def_id: DefId,
    },
    InlineAsm(Box<InlineAsmExpr<'tcx>>),
    OffsetOf {
        container: Ty<'tcx>,
        fields: &'tcx List<(VariantIdx, FieldIdx)>,
    },
    ThreadLocalRef(DefId),
    Yield {
        value: ExprId,
    },
}

Variants

Scope

Fields

region_scope: Scope

lint_level: LintLevel

value: ExprId

Scopes are used to explicitly mark destruction scopes, and to track the HirId of the expressions within the scope.

Box

Fields

value: ExprId

A box <value> expression.

If

Fields

if_then_scope: Scope

cond: ExprId

then: ExprId

else_opt: Option<ExprId>

An if expression.

Call

Fields

ty: Ty<'tcx>

The type of the function. This is often a FnDef or a FnPtr.

fun: ExprId

The function itself.

args: Box<[ExprId]>

The arguments passed to the function.

Note: in some cases (like calling a closure), the function call f(...args) gets rewritten as a call to a function trait method (e.g. FnOnce::call_once(f, (...args))).

from_hir_call: bool

Whether this is from an overloaded operator rather than a function call from HIR. true for overloaded function call.

fn_span: Span

The span of the function, without the dot and receiver (e.g. foo(a, b) in x.foo(a, b)).

A function call. Method calls and overloaded operators are converted to plain function calls.

Deref

Fields

arg: ExprId

A non-overloaded dereference.

Binary

Fields

op: BinOp

lhs: ExprId

rhs: ExprId

A non-overloaded binary operation.

LogicalOp

Fields

op: LogicalOp

lhs: ExprId

rhs: ExprId

A logical operation. This is distinct from BinaryOp because the operands need to be lazily evaluated.

Unary

Fields

op: UnOp

arg: ExprId

A non-overloaded unary operation. Note that here the deref (*) operator is represented by ExprKind::Deref.

Cast

Fields

source: ExprId

A cast: <source> as <type>. The type we cast to is the type of the parent expression.

Use

Fields

source: ExprId

Forces its contents to be treated as a value expression, not a place expression. This is inserted in some places where an operation would otherwise be erased completely (e.g. some no-op casts), but we still need to ensure that its operand is treated as a value and not a place.

NeverToAny

Fields

source: ExprId

A coercion from ! to any type.

PointerCoercion

Fields

cast: PointerCoercion

source: ExprId

A pointer coercion. More information can be found in PointerCoercion. Pointer casts that cannot be done by coercions are represented by ExprKind::Cast.

Loop

Fields

body: ExprId

A loop expression.

Let

Fields

expr: ExprId

pat: Box<Pat<'tcx>>

Special expression representing the let part of an if let or similar construct (including if let guards in match arms, and let-chains formed by &&).

This isn’t considered a real expression in surface Rust syntax, so it can only appear in specific situations, such as within the condition of an if.

(Not to be confused with StmtKind::Let, which is a normal let statement.)

Match

Fields

scrutinee: ExprId

scrutinee_hir_id: HirId

arms: Box<[ArmId]>

A match expression.

Block

Fields

block: BlockId

A block.

Assign

Fields

lhs: ExprId

rhs: ExprId

An assignment: lhs = rhs.

AssignOp

Fields

op: BinOp

lhs: ExprId

rhs: ExprId

A non-overloaded operation assignment, e.g. lhs += rhs.

Field

Fields

lhs: ExprId

variant_index: VariantIdx

Variant containing the field.

name: FieldIdx

This can be a named (.foo) or unnamed (.0) field.

Access to a field of a struct, a tuple, an union, or an enum.

Index

Fields

lhs: ExprId

index: ExprId

A non-overloaded indexing operation.

VarRef

Fields

id: LocalVarId

A local variable.

UpvarRef

Fields

closure_def_id: DefId

DefId of the closure/coroutine

var_hir_id: LocalVarId

HirId of the root variable

Used to represent upvars mentioned in a closure/coroutine

Borrow

Fields

borrow_kind: BorrowKind

arg: ExprId

A borrow, e.g. &arg.

AddressOf

Fields

mutability: Mutability

arg: ExprId

A &raw [const|mut] $place_expr raw borrow resulting in type *[const|mut] T.

Break

Fields

label: Scope

value: Option<ExprId>

A break expression.

Continue

Fields

label: Scope

A continue expression.

Return

Fields

value: Option<ExprId>

A return expression.

Become

Fields

value: ExprId

A become expression.

ConstBlock

Fields

did: DefId

args: GenericArgsRef<'tcx>

An inline const block, e.g. const {}.

Repeat

Fields

value: ExprId

count: Const<'tcx>

An array literal constructed from one repeated element, e.g. [1; 5].

Array

Fields

fields: Box<[ExprId]>

An array, e.g. [a, b, c, d].

Tuple

Fields

fields: Box<[ExprId]>

A tuple, e.g. (a, b, c, d).

Adt(Box<AdtExpr<'tcx>>)

An ADT constructor, e.g. Foo {x: 1, y: 2}.

PlaceTypeAscription

Fields

source: ExprId

user_ty: Option<Box<CanonicalUserType<'tcx>>>

Type that the user gave to this expression

A type ascription on a place.

ValueTypeAscription

Fields

source: ExprId

user_ty: Option<Box<CanonicalUserType<'tcx>>>

Type that the user gave to this expression

A type ascription on a value, e.g. 42: i32.

Closure(Box<ClosureExpr<'tcx>>)

A closure definition.

Literal

Fields

lit: &'tcx Lit

neg: bool

A literal.

NonHirLiteral

Fields

lit: ScalarInt

user_ty: Option<Box<CanonicalUserType<'tcx>>>

For literals that don’t correspond to anything in the HIR

ZstLiteral

Fields

user_ty: Option<Box<CanonicalUserType<'tcx>>>

A literal of a ZST type.

NamedConst

Fields

def_id: DefId

args: GenericArgsRef<'tcx>

user_ty: Option<Box<CanonicalUserType<'tcx>>>

Associated constants and named constants

ConstParam

Fields

param: ParamConst

def_id: DefId

StaticRef

Fields

alloc_id: AllocId

ty: Ty<'tcx>

def_id: DefId

A literal containing the address of a static.

This is only distinguished from Literal so that we can register some info for diagnostics.

InlineAsm(Box<InlineAsmExpr<'tcx>>)

Inline assembly, i.e. asm!().

OffsetOf

Fields

container: Ty<'tcx>

fields: &'tcx List<(VariantIdx, FieldIdx)>

Field offset (offset_of!)

ThreadLocalRef(DefId)

An expression taking a reference to a thread local.

Yield

Fields

value: ExprId

A yield expression.

Trait Implementations

impl<'tcx> Clone for ExprKind<'tcx>

fn clone(&self) -> ExprKind<'tcx>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'tcx> Debug for ExprKind<'tcx>

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

Formats the value using the given formatter.

impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for ExprKind<'tcx>

fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher )

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: 40 bytes

Size for each variant:

• Scope: 23 bytes
• Box: 7 bytes
• If: 23 bytes
• Call: 39 bytes
• Deref: 7 bytes
• Binary: 11 bytes
• LogicalOp: 11 bytes
• Unary: 7 bytes
• Cast: 7 bytes
• Use: 7 bytes
• NeverToAny: 7 bytes
• PointerCoercion: 7 bytes
• Loop: 7 bytes
• Let: 15 bytes
• Match: 31 bytes
• Block: 7 bytes
• Assign: 11 bytes
• AssignOp: 11 bytes
• Field: 15 bytes
• Index: 11 bytes
• VarRef: 11 bytes
• UpvarRef: 19 bytes
• Borrow: 7 bytes
• AddressOf: 7 bytes
• Break: 15 bytes
• Continue: 11 bytes
• Return: 7 bytes
• Become: 7 bytes
• ConstBlock: 23 bytes
• Repeat: 15 bytes
• Array: 23 bytes
• Tuple: 23 bytes
• Adt: 15 bytes
• PlaceTypeAscription: 15 bytes
• ValueTypeAscription: 15 bytes
• Closure: 15 bytes
• Literal: 15 bytes
• NonHirLiteral: 31 bytes
• ZstLiteral: 15 bytes
• NamedConst: 31 bytes
• ConstParam: 19 bytes
• StaticRef: 31 bytes
• InlineAsm: 15 bytes
• OffsetOf: 23 bytes
• ThreadLocalRef: 11 bytes
• Yield: 7 bytes