Struct Expr 

pub struct Expr {
    pub kind: ExprKind,
    pub span: Span,
}

An expression node in the AST.

Wraps an ExprKind discriminant with a source Span. Expressions produce values and can appear in statement position, as function arguments, in let initializers, etc.

Fields

kind: ExprKind

The kind of expression.

span: Span

Source span.

Implementations

impl Expr

pub fn child_count(&self) -> usize

Return the number of direct child expressions.

Only counts immediate children, not transitive descendants. Leaf nodes (literals, identifiers, NaLit) return 0. For Call expressions the count includes both the callee and all arguments.

Returns

The number of direct child expression sub-trees.

pub fn is_literal(&self) -> bool

Return true if this expression is a literal value.

Covers integer, float, string (including byte-string, raw-string, and raw-byte-string variants), boolean, NA, and regex literals. Collection literals (ArrayLit, TupleLit, TensorLit) are not considered literals by this method because they contain sub-expressions.

pub fn is_place(&self) -> bool

Return true if this expression is a valid assignment target (place expression).

Place expressions are identifiers, field accesses, and index accesses. These are the only forms that may appear on the left-hand side of an assignment.

pub fn is_compound(&self) -> bool

Return true if this expression is a compound (non-leaf) expression.

Compound expressions contain sub-expressions that require recursive evaluation: binary/unary operations, calls, matches, if-expressions, blocks, pipes, and lambdas.

Trait Implementations

impl Clone for Expr

fn clone(&self) -> Expr

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Expr

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

Formats the value using the given formatter.