Enum rustc_ast::ast::ExprKind [−][src]
pub enum ExprKind {
Show 42 variants
Box(P<Expr>),
Array(Vec<P<Expr>>),
ConstBlock(AnonConst),
Call(P<Expr>, Vec<P<Expr>>),
MethodCall(PathSegment, Vec<P<Expr>>, Span),
Tup(Vec<P<Expr>>),
Binary(BinOp, P<Expr>, P<Expr>),
Unary(UnOp, P<Expr>),
Lit(Lit),
Cast(P<Expr>, P<Ty>),
Type(P<Expr>, P<Ty>),
Let(P<Pat>, P<Expr>, Span),
If(P<Expr>, P<Block>, Option<P<Expr>>),
While(P<Expr>, P<Block>, Option<Label>),
ForLoop(P<Pat>, P<Expr>, P<Block>, Option<Label>),
Loop(P<Block>, Option<Label>),
Match(P<Expr>, Vec<Arm>),
Closure(CaptureBy, Async, Movability, P<FnDecl>, P<Expr>, Span),
Block(P<Block>, Option<Label>),
Async(CaptureBy, NodeId, P<Block>),
Await(P<Expr>),
TryBlock(P<Block>),
Assign(P<Expr>, P<Expr>, Span),
AssignOp(BinOp, P<Expr>, P<Expr>),
Field(P<Expr>, Ident),
Index(P<Expr>, P<Expr>),
Range(Option<P<Expr>>, Option<P<Expr>>, RangeLimits),
Underscore,
Path(Option<QSelf>, Path),
AddrOf(BorrowKind, Mutability, P<Expr>),
Break(Option<Label>, Option<P<Expr>>),
Continue(Option<Label>),
Ret(Option<P<Expr>>),
InlineAsm(P<InlineAsm>),
LlvmInlineAsm(P<LlvmInlineAsm>),
MacCall(MacCall),
Struct(P<StructExpr>),
Repeat(P<Expr>, AnonConst),
Paren(P<Expr>),
Try(P<Expr>),
Yield(Option<P<Expr>>),
Err,
}Variants
Box(P<Expr>)
A box x expression.
Array(Vec<P<Expr>>)
An array ([a, b, c, d])
ConstBlock(AnonConst)
Tuple Fields
0: AnonConstAllow anonymous constants from an inline const block
Call(P<Expr>, Vec<P<Expr>>)
A function call
The first field resolves to the function itself, and the second field is the list of arguments. This also represents calling the constructor of tuple-like ADTs such as tuple structs and enum variants.
MethodCall(PathSegment, Vec<P<Expr>>, Span)
A method call (x.foo::<'static, Bar, Baz>(a, b, c, d))
The PathSegment represents the method name and its generic arguments
(within the angle brackets).
The first element of the vector of an Expr is the expression that evaluates
to the object on which the method is being called on (the receiver),
and the remaining elements are the rest of the arguments.
Thus, x.foo::<Bar, Baz>(a, b, c, d) is represented as
ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d]).
This Span is the span of the function, without the dot and receiver
(e.g. foo(a, b) in x.foo(a, b)
Tup(Vec<P<Expr>>)
A tuple (e.g., (a, b, c, d)).
Binary(BinOp, P<Expr>, P<Expr>)
A binary operation (e.g., a + b, a * b).
Unary(UnOp, P<Expr>)
A unary operation (e.g., !x, *x).
Lit(Lit)
Tuple Fields
0: LitA literal (e.g., 1, "foo").
Cast(P<Expr>, P<Ty>)
A cast (e.g., foo as f64).
Type(P<Expr>, P<Ty>)
A type ascription (e.g., 42: usize).
Let(P<Pat>, P<Expr>, Span)
A let pat = expr expression that is only semantically allowed in the condition
of if / while expressions. (e.g., if let 0 = x { .. }).
Span represents the whole let pat = expr statement.
If(P<Expr>, P<Block>, Option<P<Expr>>)
An if block, with an optional else block.
if expr { block } else { expr }
While(P<Expr>, P<Block>, Option<Label>)
A while loop, with an optional label.
'label: while expr { block }
ForLoop(P<Pat>, P<Expr>, P<Block>, Option<Label>)
A for loop, with an optional label.
'label: for pat in expr { block }
This is desugared to a combination of loop and match expressions.
Loop(P<Block>, Option<Label>)
Conditionless loop (can be exited with break, continue, or return).
'label: loop { block }
Match(P<Expr>, Vec<Arm>)
A match block.
Closure(CaptureBy, Async, Movability, P<FnDecl>, P<Expr>, Span)
A closure (e.g., move |a, b, c| a + b + c).
The final span is the span of the argument block |...|.
Block(P<Block>, Option<Label>)
A block ('label: { ... }).
Async(CaptureBy, NodeId, P<Block>)
An async block (async move { ... }).
The NodeId is the NodeId for the closure that results from
desugaring an async block, just like the NodeId field in the
Async::Yes variant. This is necessary in order to create a def for the
closure which can be used as a parent of any child defs. Defs
created during lowering cannot be made the parent of any other
preexisting defs.
Await(P<Expr>)
An await expression (my_future.await).
TryBlock(P<Block>)
A try block (try { ... }).
Assign(P<Expr>, P<Expr>, Span)
An assignment (a = foo()).
The Span argument is the span of the = token.
AssignOp(BinOp, P<Expr>, P<Expr>)
An assignment with an operator.
E.g., a += 1.
Field(P<Expr>, Ident)
Access of a named (e.g., obj.foo) or unnamed (e.g., obj.0) struct field.
Index(P<Expr>, P<Expr>)
An indexing operation (e.g., foo[2]).
Range(Option<P<Expr>>, Option<P<Expr>>, RangeLimits)
A range (e.g., 1..2, 1.., ..2, 1..=2, ..=2; and .. in destructuring assignment).
Underscore
An underscore, used in destructuring assignment to ignore a value.
Path(Option<QSelf>, Path)
Variable reference, possibly containing :: and/or type
parameters (e.g., foo::bar::<baz>).
Optionally “qualified” (e.g., <Vec<T> as SomeTrait>::SomeType).
AddrOf(BorrowKind, Mutability, P<Expr>)
A referencing operation (&a, &mut a, &raw const a or &raw mut a).
Break(Option<Label>, Option<P<Expr>>)
A break, with an optional label to break, and an optional expression.
Continue(Option<Label>)
A continue, with an optional label.
Ret(Option<P<Expr>>)
A return, with an optional value to be returned.
InlineAsm(P<InlineAsm>)
Output of the asm!() macro.
LlvmInlineAsm(P<LlvmInlineAsm>)
Tuple Fields
0: P<LlvmInlineAsm>Output of the llvm_asm!() macro.
MacCall(MacCall)
Tuple Fields
0: MacCallA macro invocation; pre-expansion.
Struct(P<StructExpr>)
Tuple Fields
0: P<StructExpr>A struct literal expression.
E.g., Foo {x: 1, y: 2}, or Foo {x: 1, .. rest}.
Repeat(P<Expr>, AnonConst)
An array literal constructed from one repeated element.
E.g., [1; 5]. The expression is the element to be
repeated; the constant is the number of times to repeat it.
Paren(P<Expr>)
No-op: used solely so we can pretty-print faithfully.
Try(P<Expr>)
A try expression (expr?).
Yield(Option<P<Expr>>)
A yield, with an optional value to be yielded.
Err
Placeholder for an expression that wasn’t syntactically well formed in some way.
Trait Implementations
Auto Trait Implementations
impl !RefUnwindSafe for ExprKind
impl !UnwindSafe for ExprKind
Blanket Implementations
Mutably borrows from an owned value. Read more
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: 72 bytes
Size for each variant:
Box: 15 bytesArray: 31 bytesConstBlock: 23 bytesCall: 39 bytesMethodCall: 63 bytesTup: 31 bytesBinary: 31 bytesUnary: 15 bytesLit: 55 bytesCast: 23 bytesType: 23 bytesLet: 31 bytesIf: 31 bytesWhile: 31 bytesForLoop: 39 bytesLoop: 23 bytesMatch: 39 bytesClosure: 47 bytesBlock: 23 bytesAsync: 15 bytesAwait: 15 bytesTryBlock: 15 bytesAssign: 31 bytesAssignOp: 31 bytesField: 23 bytesIndex: 23 bytesRange: 23 bytesUnderscore: 0 bytesPath: 71 bytesAddrOf: 15 bytesBreak: 23 bytesContinue: 15 bytesRet: 15 bytesInlineAsm: 15 bytesLlvmInlineAsm: 15 bytesMacCall: 71 bytesStruct: 15 bytesRepeat: 31 bytesParen: 15 bytesTry: 15 bytesYield: 15 bytesErr: 0 bytes