Expand description
The Rust abstract syntax tree module.
This module contains common structures forming the language AST.
Two main entities in the module are Item (which represents an AST element with
additional metadata), and ItemKind (which represents a concrete type and contains
information specific to the type of the item).
Other module items worth mentioning:
TyandTyKind: A parsed Rust type.ExprandExprKind: A parsed Rust expression.PatandPatKind: A parsed Rust pattern. Patterns are often dual to expressions.StmtandStmtKind: An executable action that does not return a value.FnDecl,FnHeaderandParam: Metadata associated with a function declaration.Generics,GenericParam,WhereClause: Metadata associated with generic parameters.EnumDefandVariant: Enum declaration.MetaItemLitandLitKind: Literal expressions.MacroDef,MacStmtStyle,MacCall,MacDelimiter: Macro definition and invocation.Attribute: Metadata associated with item.UnOp,BinOp, andBinOpKind: Unary and binary operators.
Re-exports
pub use crate::util::parser::ExprPrecedence;pub use crate::node_id::NodeId;pub use crate::node_id::CRATE_NODE_ID;pub use crate::node_id::DUMMY_NODE_ID;pub use GenericArgs::*;pub use UnsafeSource::*;Modules
Structs
A path like
Foo<'a, T>.A constant (expression) that’s not an item or associated item,
but needs its own
DefId for type-checking, const-eval, etc.
These are usually found nested inside types (e.g., array lengths)
or expressions (e.g., repeat counts), and also used to define
explicit discriminant values for enum variants.An arm of a ‘match’.
A constraint on an associated type (e.g.,
A = Bar in Foo<A = Bar> or
A: TraitA + TraitB in Foo<A: TraitA + TraitB>).A syntax-level representation of an attribute.
Explicit binding annotations given in the HIR for a binding. Note
that this is not the final binding mode that we infer after type
inference.
A block (
{ .. }).Delimited arguments, as used in
#[attr()/[]/{}] or mac!()/[]/{}.An expression.
A single field in a struct expression, e.g.
x: value and y in Foo { x: value, y }.Field definition in a struct, variant or union.
A signature (not the body) of a function declaration.
A function header.
Represents a function’s signature in a trait declaration,
trait implementation, or free function.
Foreign module declaration.
Represents lifetime, type and const parameters attached to a declaration of
a function, enum, trait, etc.
Inline assembly.
Inline assembly symbol operands get their own AST node that is somewhat
similar to
AnonConst.An item definition.
A “Label” is an identifier of some point in sources,
e.g. in the following code:
A “Lifetime” is an annotation of the scope in which variable
can be used, e.g.
'a in &'a i32.Local represents a
let statement, e.g., let <pat>:<ty> = <expr>;.Represents a macro invocation. The
path indicates which macro
is being invoked, and the args are arguments passed to it.Represents a macro definition.
A semantic representation of a meta item. A meta item is a slightly
restricted form of an attribute – it can only contain expressions in
certain leaf positions, rather than arbitrary token streams – that is used
for most built-in attributes.
A literal in a meta item.
A method call (e.g.
x.foo::<Bar, Baz>(a, b, c)).A parameter in a function header.
A path like
Foo(A, B) -> C.A match pattern.
A single field in a struct pattern.
A “Path” is essentially Rust’s notion of a name.
A segment of a path: an identifier, an optional lifetime, and a set of types.
The explicit
Self type in a “qualified path”. The actual
path, including the trait and the associated item, is stored
separately. position represents the index of the associated
item qualified with this Self type.A statement
Similar to
MetaItemLit, but restricted to string literals.TraitRefs appear in impls.The location of a where clause on a
TyAlias (Span) and whether there was
a where keyword (bool). This is split out from WhereClause, since there
are two locations for where clause on type aliases, but their predicates
are concatenated together.A tree of paths sharing common prefixes.
Used in
use items both at top-level and inside of braces in import groups.Enum variant.
A type bound.
A where-clause in a definition.
An equality predicate (unsupported).
A lifetime predicate.
Enums
Either an argument for a parameter e.g.,
'a, Vec<u8>, 0,
or a constraint on an associated item, e.g., Item = String or Item: Bound.The kinds of an
AssocConstraint.Represents associated item kinds.
Arguments passed to an attribute macro.
Distinguishes between
Attributes that decorate items and Attributes that
are contained as statements within items. These two cases need to be
distinguished for pretty-printing.The kind of borrow in an
AddrOf expression,
e.g., &place or &raw const place.A capture clause used in closures and
async blocks.Closure lifetime binder,
for<'a, 'b> in for<'a, 'b> |_: &'a (), _: &'b ()|.Item defaultness.
For details see the RFC #2532.
extern qualifier on a function item or function type.An item in
extern block.Concrete argument in the sequence of generic args.
The arguments of a path segment.
The AST represents all type param bounds as types.
typeck::collect::compute_bounds matches these against
the “special” built-in traits (see middle::lang_items) and
detects Copy, Send and Sync.Inline assembly operand.
Inline assembly operand explicit register or register class.
Is the trait definition an auto trait?
Type of the float literal based on provided suffix.
Type of the integer literal based on provided suffix.
This type is used within both
ast::MetaItemLit and hir::Lit.The meta item kind, containing the data after the initial path.
Module item kind.
The movability of a generator / closure literal:
whether a generator contains self-references, causing it to be
!Unpin.Values inside meta item lists.
Specifies the enforced ordering for generic parameters. In the future,
if we wanted to relax this order, we could override
PartialEq and
PartialOrd, to allow the kinds to be unordered.All the different flavors of pattern that Rust recognizes.
Limit types of a range (inclusive or exclusive)
Alternative representation for
Args describing self parameter of methods.The kinds of an
AssocConstraint.A modifier on a bound, e.g.,
?Trait or ~const Trait.Syntax used to declare a trait object.
The various kinds of type recognized by the compiler.
Unary operator.
Part of
use item to the right of its prefix.Fields and constructor ids of enum variants and structs.
A single predicate in a where-clause.
Type Definitions
Represents associated items.
These include items in
impl and trait definitions.A list of attributes.