Struct PhysicalExprDecodeCtx 

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

Available on crate feature proto only.

Decoder context handed to per-expression try_from_proto constructors.

Wraps an internal PhysicalExprDecode trait object plus a borrowed schema. The trait stays an implementation detail of datafusion-proto; expression authors only see this struct.

Implementations

impl<'a> PhysicalExprDecodeCtx<'a>

pub fn new(schema: &'a Schema, decoder: &'a dyn PhysicalExprDecode) -> Self

Construct a new decode context. Typically called by datafusion-proto; expression authors receive &PhysicalExprDecodeCtx.

pub fn schema(&self) -> &Schema

The schema bound to this decode context. Use it for column lookups, data-type resolution, etc.

pub fn decode(&self, node: &PhysicalExprNode) -> Result<Arc<dyn PhysicalExpr>>

Decode an expression node, recursing into child sub-expressions.

Routes built-in ExprType variants through datafusion-proto’s central match and forwards extension nodes to the registered codec (today via PhysicalExtensionCodec::try_decode_expr; later via a per-type registry — see #21835).

pub fn decode_required_expression( &self, node: Option<&PhysicalExprNode>, expr_name: &str, field: &str, ) -> Result<Arc<dyn PhysicalExpr>>

Decode a required child node, erroring if it is absent.

Proto child expressions are encoded as Option<Box<PhysicalExprNode>>; pass the field directly (e.g. node.expr.as_deref()). expr_name is the expression being decoded (e.g. "InListExpr") and field the proto field (e.g. "expr"); both are woven into the error so it names where the missing field is, without each author hand-rolling the string.

pub fn decode_children_expressions<'b, I>( &self, nodes: I, ) -> Result<Vec<Arc<dyn PhysicalExpr>>>

where I: IntoIterator<Item = &'b PhysicalExprNode>,

Decode a sequence of child nodes, preserving order.

Convenience wrapper over Self::decode for expressions holding a repeated proto field (e.g. the list of an InList). The first decode error short-circuits.