Enum tidb_query_expr::types::RpnStackNode

pub enum RpnStackNode<'a> {
    Scalar {
        value: &'a ScalarValue,
        field_type: &'a FieldType,
    },
    Vector {
        value: RpnStackNodeVectorValue<'a>,
        field_type: &'a FieldType,
    },
}

A type for each node in the RPN evaluation stack. It can be one of a scalar value node or a vector value node. The vector value node can be either an owned vector value or a reference.

Variants

Scalar

Represents a scalar value. Comes from a constant node in expression list.

Fields of Scalar

value: &'a ScalarValuefield_type: &'a FieldType

Vector

Represents a vector value. Comes from a column reference or evaluated result.

Fields of Vector

value: RpnStackNodeVectorValue<'a>field_type: &'a FieldType

Implementations

impl<'a> RpnStackNode<'a>

pub fn field_type(&self) -> &FieldType

Gets the field type.

pub fn scalar_value(&self) -> Option<&ScalarValue>

Borrows the inner scalar value for Scalar variant.

pub fn vector_value(&self) -> Option<&RpnStackNodeVectorValue<'_>>

Borrows the inner vector value for Vector variant.

pub fn is_scalar(&self) -> bool

Whether this is a Scalar variant.

pub fn is_vector(&self) -> bool

Whether this is a Vector variant.

pub fn get_logical_scalar_ref(&self, logical_index: usize) -> ScalarValueRef<'_>

Gets a reference of the element by logical index.

If this is a Scalar variant, the returned reference will be the same for any index.

Panics

Panics if index is out of range and this is a Vector variant.

Trait Implementations

impl<'a> Debug for RpnStackNode<'a>

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

Formats the value using the given formatter.