Enum Value 

pub enum Value<N> {
    NodeSet(Vec<N>),
    Boolean(bool),
    Number(f64),
    String(String),
}

An XPath 1.0 value: one of the four object types (§3.1) — “node-set (an unordered collection of nodes without duplicates), boolean, number … [or] string”.

Parameterized only over the node type N, not over a separate lifetime — a concrete N already implements Node<'a> for one specific 'a (e.g. TestNode<'a>), so that lifetime doesn’t need to be repeated here (the plan’s sketched Value<'a, N: Node<'a>> shape is adjusted to avoid an otherwise-unused lifetime parameter on the enum itself).

Variants

NodeSet(Vec<N>)

Boolean(bool)

Number(f64)

An IEEE-754 double-precision floating point number.

String(String)

Implementations

impl<'a, N: Node<'a>> Value<N>

pub fn to_boolean(&self) -> bool

§4.3, verbatim: “a number is true if and only if it is neither positive or negative zero nor NaN; a node-set is true if and only if it is non-empty; a string is true if and only if its length is non-zero”.

pub fn to_number(&self) -> f64

§4.4: string→number (via the node-set→string→number chain for node-sets), boolean→number (“true is converted to 1; false to 0”), and the identity for numbers.

pub fn to_xpath_string(&self) -> String

§4.2: node-set→string (“the string-value of the node … that is first in document order. If the node-set is empty, an empty string is returned”), number→string (see number_to_string), and boolean→string (“false”/“true”).

Named to_xpath_string rather than to_string so this inherent method does not collide with (and get flagged by clippy as shadowing) std::string::ToString — Value deliberately does not implement Display/ToString.

Trait Implementations

impl<N: Clone> Clone for Value<N>

fn clone(&self) -> Value<N>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<N: Debug> Debug for Value<N>

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

Formats the value using the given formatter.

impl<N: PartialEq> PartialEq for Value<N>

fn eq(&self, other: &Value<N>) -> bool

Equality operator ==.

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

Inequality operator !=.

impl<N: PartialEq> StructuralPartialEq for Value<N>