Struct HierarchicalActivation 

pub struct HierarchicalActivation<'a> { /* private fields */ }

A hierarchical activation that delegates to a parent if not found locally.

This is useful for implementing variable scopes in comprehensions where iteration variables shadow outer variables.

Implementations

impl<'a> HierarchicalActivation<'a>

pub fn new(parent: &'a dyn Activation) -> Self

Create a new hierarchical activation with a parent.

pub fn with_binding( self, name: impl Into<String>, value: impl Into<Value>, ) -> Self

Add a local binding that shadows the parent.

pub fn insert(&mut self, name: impl Into<String>, value: impl Into<Value>)

Insert a local binding.

pub fn remove(&mut self, name: &str) -> Option<Value>

Remove a local binding.

Trait Implementations

impl Activation for HierarchicalActivation<'_>

fn resolve(&self, name: &str) -> Option<Value>

Resolve a variable name to its value.

fn has(&self, name: &str) -> bool

Check if a variable is defined (present check for has() macro).