Struct Expr 

pub struct Expr<T> { /* private fields */ }

A parse-checked Jetro expression with a phantom output type.

The phantom T captures the caller’s intent about the result shape and is used by typed accessors (e.g. Bucket::get_as) to drive serde deserialisation. It is not statically verified — constructing an Expr<u64> from an expression that yields a string is possible; the mismatch surfaces at evaluation time as a deserialisation error.

Implementations

impl<T> Expr<T>

pub fn new<S: Into<String>>(src: S) -> Result<Self, Error>

Parse and wrap src. Returns Error::Parse if the expression is not syntactically valid.

pub fn as_str(&self) -> &str

Raw source text — useful for storing in an [ExprBucket] or for debugging.

pub fn into_string(self) -> String

Discard the phantom output type. Rarely needed; cast::<U> is usually what callers want.

pub fn cast<U>(self) -> Expr<U>

Re-tag the expression with a different phantom output type. No reparse; cheap.

impl<T: DeserializeOwned> Expr<T>

pub fn eval(&self, doc: &Value) -> Result<T, Error>

Evaluate self against doc, returning a typed value.

Goes through a fresh VM — for repeated evaluations prefer Expr::eval_with so caches accumulate.

pub fn eval_with(&self, vm: &mut VM, doc: &Value) -> Result<T, Error>

Evaluate with a caller-supplied VM so its compile and resolution caches are shared across calls.

impl Expr<Value>

pub fn eval_raw(&self, doc: &Value) -> Result<Value, Error>

Evaluate and return the raw Value without deserialisation.

Trait Implementations

impl<T> AsRef<str> for Expr<T>

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl<T, U> BitOr<Expr<U>> for Expr<T>

a | b → expression source "(a) | (b)". The resulting type is Expr<U> since the right-hand side determines the output shape.

type Output = Expr<U>

The resulting type after applying the | operator.

fn bitor(self, rhs: Expr<U>) -> Expr<U>

Performs the | operation.

impl<T: Clone> Clone for Expr<T>

fn clone(&self) -> Expr<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Expr<T>

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

Formats the value using the given formatter.

impl<T> Display for Expr<T>

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

Formats the value using the given formatter.