Struct Binding 

pub struct Binding {
    pub bound: VariableSet,
    /* private fields */
}

The binding keeps track of the values assigned to variables in a query. It maps variables to values - by their index - via a simple array, and keeps track of which variables are bound. It is used to store intermediate results and to pass information between different constraints. The binding is mutable, as it is modified by the query engine. It is not thread-safe and should not be shared between threads. The binding is a simple data structure that is cheap to clone. It is not intended to be used as a long-term storage for query results.

Fields

bound: VariableSet

Bitset tracking which variables have been assigned a value.

Implementations

impl Binding

pub fn set(&mut self, variable: VariableId, value: &RawValue)

Binds variable to value.

pub fn unset(&mut self, variable: VariableId)

Unset a variable in the binding. This is used to backtrack in the query engine.

pub fn get(&self, variable: VariableId) -> Option<&RawValue>

Check if a variable is bound in the binding.

Trait Implementations

impl Clone for Binding

fn clone(&self) -> Binding

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Binding

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

Formats the value using the given formatter.

impl Default for Binding

fn default() -> Self

Returns the “default value” for a type.