Struct BodyColumnI32 

pub struct BodyColumnI32 {
    pub column: String,
    /* private fields */
}

body_column_i32(body, "name") — extract the named column from every row of a JSON result body, parse each as i32, and return the values as a VecI32 wire.

This is the canonical capture path for tabular result data into typed-vector wires. Adapter result bodies that already serialize to [{ "key": 1, ... }, { "key": 2, ... }, ...]-shaped JSON can expose per-column wires for downstream readers (the recall evaluator, custom metrics, etc.) without forcing string round-trips through the metric reader.

Robust extraction rules:

• Body shape [{...}, {...}, ...]: walks each row, looks up the column by name, parses as i32 via json_value_as_i32.
• Body shape { "rows": [...] }: walks rows; same per-row extraction as above. Matches common envelope formats (Jolokia, HTTP wrappers).
• Body shape { "key": value, ... } (single row at top level): produces a single-element vector.
• Non-JSON input: empty vector. This preserves the “no values extracted” diagnostic at the evaluator instead of panicking here.

Rows whose column is absent / null / unparseable contribute nothing (no zero-fill, no error). Mirrors the legacy host-side extract_indices_from_json JSON-walk so workloads can swap to this typed-wire path without recall-value drift.

The body is a PolyWire so the non-Json fallback (“empty vector, no panic”) applies; column is a const string with no default (required workload arg).

Fields

column: String

The column argument, as given at construction.

Implementations

impl BodyColumnI32

pub fn new(body_type: PortType, column: String) -> Self

A body_column_i32 node with the given constant arguments.

Trait Implementations

impl PolydatNode for BodyColumnI32

fn meta(&self) -> &NodeMeta

Return this node’s metadata (port names and types).

fn eval(&self, inputs: &[Value], outputs: &mut [Value])

Evaluate the node: read from inputs, write to outputs.

fn compiled_slot(&self, wire_types: &[PortType]) -> Option<CompiledSlotKit>

Return a slot-compiled closure for nodes with typed-slice ports (§8.4 layer 3): slice inputs read (ptr, len) slot pairs; vector outputs write into kernel-owned scratch. Checked by the compiled-kernel builders AFTER Self::compiled_u64 — pure-scalar nodes never need it. Default None: the node stays on typed eval.

fn accepts_none_inputs(&self) -> bool

True iff this node should receive Value::None inputs directly rather than have the kernel propagate None through it. Default: false — most nodes follow SRD-74 Rule 1 (None in → None out, no eval invocation).

fn scratch_layout(&self) -> Vec<ScratchElem>

The scratch entries a state owns for this node’s evaluation (axiom S3), one per entry in the order the node expects them in Self::eval_in. Empty for a node that evaluates over Values alone, which is every node but a native cone.

fn eval_in( &self, scratch: &mut [ScratchBuf], inputs: &[Value], outputs: &mut [Value], )

Self::eval with the node’s scratch, which the evaluating state owns and hands in: storage belongs to the state, never to the node, which is shared by every state of the program.

fn commutativity(&self) -> Commutativity

Declare which inputs are interchangeable for this node.

fn compiled_u64(&self) -> Option<CompiledU64Op>

Return a compiled u64-only evaluation closure, if this node operates entirely in u64 space.

fn jit_constants(&self) -> Vec<u64>

Return assembly-time constants for JIT compilation.

fn purity(&self) -> Purity

Declare this node’s purity status per the runtime_model.md’s D2 axiom. Default: Purity::Pure. Override to declare an observable side channel (Purity::SideChannel) or eval-call-spanning state (Purity::Nondeterministic).

fn simd_variant(&self) -> Option<SimdVariant>

Explicit SIMD-native implementation of this scalar node, if one has been registered with a semantic contract.

fn fusion_subgraph(&self) -> Option<FusionSubgraph<'_>>

A synthetic fusion node’s view of the subgraph it stands in for (SRD-105 cone extraction). Program-identity hashing (PolydatProgram::canonical_hash) walks THROUGH fusion nodes into this subgraph, so identity is invariant to the engine mix: jit=off and jit=auto compiles of the same source hash identically, and resume-skip matching survives mode changes. Default None: ordinary nodes hash as themselves.