Struct DynamicContext 

pub struct DynamicContext<'a, N: DomNavigator> {
    pub static_context: &'a XPathContext<'a>,
    pub context_item: Option<XmlItem<N>>,
    pub context_position: usize,
    pub context_size: usize,
    pub current_datetime: Option<DateTimeValue>,
    pub implicit_timezone: Option<TimezoneOffset>,
    pub base_uri: Option<String>,
    pub variables: VarStore<XPathValue<N>>,
    /* private fields */
}

XPath 2.0 dynamic context for expression evaluation.

The dynamic context provides runtime information:

• Current context item (node or atomic value)
• Context position and size (for predicates)
• Variable bindings (indexed by VarSlotId)
• Current date/time (stable for duration of query)
• Implicit timezone

Fields

static_context: &'a XPathContext<'a>

Reference to the static context

context_item: Option<XmlItem<N>>

Current context item (if any)

context_position: usize

Current context position (1-based)

context_size: usize

Current context size

current_datetime: Option<DateTimeValue>

Current date/time (stable for entire query evaluation)

implicit_timezone: Option<TimezoneOffset>

Implicit timezone

base_uri: Option<String>

Base URI for resolving relative URIs

variables: VarStore<XPathValue<N>>

Variable bindings (indexed by VarSlotId from NameBinder)

Implementations

impl<'a, N: DomNavigator> DynamicContext<'a, N>

pub fn new(static_context: &'a XPathContext<'a>, var_count: usize) -> Self

Create a new dynamic context with the given static context.

The var_count should be NameBinder::len() after binding.

pub fn with_context_item(self, item: XmlItem<N>) -> Self

Set the context item.

pub fn with_context_node(self, node: N) -> Self

Set the context node.

pub fn with_position(self, position: usize, size: usize) -> Self

Set context position and size (for predicate evaluation).

pub fn with_current_datetime(self, dt: DateTimeValue) -> Self

Set the current date/time.

pub fn with_implicit_timezone(self, tz: TimezoneOffset) -> Self

Set the implicit timezone.

pub fn require_context_item(&self) -> Result<&XmlItem<N>, XPathError>

Get the context item, returning an error if undefined.

pub fn require_context_node(&self) -> Result<&N, XPathError>

Get the context node, returning an error if undefined or not a node.

Returns XPTY0020 if the context item is not a node (per XPath 2.0 spec for axis steps).

pub fn get_variable(&self, slot: VarSlotId) -> Option<&XPathValue<N>>

Get a variable value by slot ID.

pub fn set_variable(&mut self, slot: VarSlotId, value: XPathValue<N>)

Set a variable value.

pub fn with_function_evaluator( self, evaluator: &'a dyn FunctionEvaluator<N>, ) -> Self

Set the function evaluator for custom function support.

pub fn function_evaluator(&self) -> &dyn FunctionEvaluator<N>

Get the function evaluator, using built-in functions as default.

Returns a reference to the configured evaluator, or BuiltinEvaluator if none set.

pub fn has_custom_evaluator(&self) -> bool

Check if a custom function evaluator is configured.

pub fn eval_function( &mut self, handle: FunctionHandle, args: Vec<XPathValue<N>>, ) -> Result<XPathValue<N>, XPathError>

Evaluate a function using the configured evaluator.

This method exists to work around borrow checker issues with calling self.function_evaluator().eval(handle, self, args) where the evaluator borrow conflicts with the mutable self borrow.