Struct Scope

pub struct Scope { /* private fields */ }

Scope define the evaluation context/scope that an expression uses when being evaluated. There is a special Identifier (Identity) which is used to bind the initial array being evaluated

Other identifier can be bound with variables either before execution or while executing (see Let). Values can be extracted from the scope using the Var expression.

<let x = lit(1) in var(Identifier::Identity) + var(x), { Identity -> Primitive[1,2,3]> ->
<var(Identifier::Identity) + var(x), { Identity -> Primitive[1,2,3], x -> ConstantArray(1)> ->
<Primitive[1,2,3] + var(x), { Identity -> Primitive[1,2,3], x -> ConstantArray(1)> ->
<Primitive[1,2,3] + ConstantArray(1), { Identity -> Primitive[1,2,3], x -> ConstantArray(1)> ->
<Primitive[2,3,4], { Identity -> Primitive[1,2,3], x -> ConstantArray(1)>

Other values can be bound before execution e.g. <var("x") + var("y") + var("z"), x -> ..., y -> ..., z -> ...>

Implementations

impl Scope

pub fn new(arr: ArrayRef) -> Self

pub fn empty(len: usize) -> Self

pub fn array(&self, id: &Identifier) -> Option<&ArrayRef>

Get a value out of the scope by its Identifier

pub fn vars(&self, id: Identifier) -> VortexResult<&Arc<dyn Any + Send + Sync>>

pub fn is_empty(&self) -> bool

pub fn len(&self) -> usize

pub fn copy_with_array(&self, ident: Identifier, value: ArrayRef) -> Self

pub fn with_array(self, ident: Identifier, value: ArrayRef) -> Self

Register an array with an identifier in the scope, overriding any existing value stored in it.

pub fn with_array_pair(self, (ident, value): ScopeElement) -> Self

Register an array with an identifier in the scope, overriding any existing value stored in it.

pub fn with_var( self, ident: Identifier, var: Arc<dyn Any + Send + Sync>, ) -> Self

pub fn with_scope_var<V: ScopeVar>(self, var: V) -> Self

Returns a new evaluation scope with the given variable applied.

pub fn scope_var<V: ScopeVar>(&self) -> Option<&V>

Returns the scope variable of type V if it exists.

pub fn scope_var_mut<V: ScopeVar>(&mut self) -> Option<&mut V>

Returns the mutable scope variable of type V if it exists.

pub fn iter(&self) -> impl Iterator<Item = (&Identifier, &ArrayRef)>

Trait Implementations

impl Clone for Scope

fn clone(&self) -> Scope

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for Scope

fn default() -> Scope

Returns the “default value” for a type.

impl From<&Scope> for ScopeDType

fn from(ctx: &Scope) -> Self

Converts to this type from the input type.

impl From<Arc<dyn Array>> for Scope

fn from(value: ArrayRef) -> Self

Converts to this type from the input type.