pub enum ExprKind {
Show 43 variants
Box(P<Expr>),
Array(Vec<P<Expr>>),
ConstBlock(AnonConst),
Call(P<Expr>, Vec<P<Expr>>),
MethodCall(Box<MethodCall>),
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>, Span),
Match(P<Expr>, Vec<Arm>),
Closure(Box<Closure>),
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<P<QSelf>>, Path),
AddrOf(BorrowKind, Mutability, P<Expr>),
Break(Option<Label>, Option<P<Expr>>),
Continue(Option<Label>),
Ret(Option<P<Expr>>),
InlineAsm(P<InlineAsm>),
MacCall(P<MacCall>),
Struct(P<StructExpr>),
Repeat(P<Expr>, AnonConst),
Paren(P<Expr>),
Try(P<Expr>),
Yield(Option<P<Expr>>),
Yeet(Option<P<Expr>>),
IncludedBytes(Lrc<[u8]>),
Err,
}
Variants§
Box(P<Expr>)
A box x
expression.
Array(Vec<P<Expr>>)
An array ([a, b, c, d]
)
ConstBlock(AnonConst)
Allow 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(Box<MethodCall>)
A method call (e.g. x.foo::<Bar, Baz>(a, b, c)
).
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)
A 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>, Span)
Conditionless loop (can be exited with break
, continue
, or return
).
'label: loop { block }
Match(P<Expr>, Vec<Arm>)
A match
block.
Closure(Box<Closure>)
A closure (e.g., move |a, b, c| a + b + c
).
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<P<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.
MacCall(P<MacCall>)
A macro invocation; pre-expansion.
Struct(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.
Yeet(Option<P<Expr>>)
A do yeet
(aka throw
/fail
/bail
/raise
/whatever),
with an optional value to be returned.
IncludedBytes(Lrc<[u8]>)
Bytes included via include_bytes!
Added for optimization purposes to avoid the need to escape
large binary blobs - should always behave like ExprKind::Lit
with a ByteStr
literal.
Err
Placeholder for an expression that wasn’t syntactically well formed in some way.
Trait Implementations§
Auto Trait Implementations§
impl !RefUnwindSafe for ExprKind
impl !Send for ExprKind
impl !Sync for ExprKind
impl Unpin for ExprKind
impl !UnwindSafe for ExprKind
Blanket Implementations§
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:
Box
: 15 bytesArray
: 31 bytesConstBlock
: 23 bytesCall
: 39 bytesMethodCall
: 15 bytesTup
: 31 bytesBinary
: 31 bytesUnary
: 15 bytesLit
: 15 bytesCast
: 23 bytesType
: 23 bytesLet
: 31 bytesIf
: 31 bytesWhile
: 31 bytesForLoop
: 39 bytesLoop
: 31 bytesMatch
: 39 bytesClosure
: 15 bytesBlock
: 23 bytesAsync
: 15 bytesAwait
: 15 bytesTryBlock
: 15 bytesAssign
: 31 bytesAssignOp
: 31 bytesField
: 23 bytesIndex
: 23 bytesRange
: 23 bytesUnderscore
: 0 bytesPath
: 39 bytesAddrOf
: 15 bytesBreak
: 23 bytesContinue
: 15 bytesRet
: 15 bytesInlineAsm
: 15 bytesMacCall
: 15 bytesStruct
: 15 bytesRepeat
: 31 bytesParen
: 15 bytesTry
: 15 bytesYield
: 15 bytesYeet
: 15 bytesIncludedBytes
: 23 bytesErr
: 0 bytes