Enum Expr 

pub enum Expr {
    Lit(f64),
    Var(Var),
    Unary(UnaryOp, Box<Expr>),
    Binary(BinOp, Box<Expr>, Box<Expr>),
    Call(Func, Vec<Expr>),
}

An argument expression, evaluated per shape at derivation time.

Variants

Lit(f64)

Literal constant. The only node genetics mutates.

Var(Var)

Unary(UnaryOp, Box<Expr>)

Binary(BinOp, Box<Expr>, Box<Expr>)

Call(Func, Vec<Expr>)

Implementations

impl Expr

pub fn lit(v: f64) -> Self

Convenience literal constructor.

pub fn node_count(&self) -> usize

Total AST node count (self included). Used for the MAX_EXPR_NODES DoS cap and as a cheap complexity metric.

pub fn as_lit(&self) -> Option<f64>

Some(v) when the expression is a bare literal. Parse-time range checks apply only to bare literals; everything else re-validates at evaluation time.

pub fn visit_literals_mut(&mut self, f: &mut impl FnMut(&mut f64))

Visits every literal leaf mutably — the genetics mutation hook.

pub fn shape_eq(&self, other: &Expr) -> bool

Structural equality that ignores literal values — two expressions have the same shape when they differ only in their Lit payloads. Genetics uses this to decide whether two ops are crossover-compatible.

impl Expr

pub fn eval(&self, ctx: &mut EvalCtx<'_>) -> Result<f64, ShapeError>

Evaluates the expression. Any non-finite intermediate or final result is an error — scope math must stay finite.

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.

impl<'de> Deserialize<'de> for Expr

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Expr

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

Renders with explicit parentheses around every compound node — unambiguous by construction, at the cost of elegance. Guarantees parse(display(e)) reproduces e (asserted in tests).

impl PartialEq for Expr

fn eq(&self, other: &Expr) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for Expr

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Expr