Enum Binder 

pub enum Binder {
    Positional {
        field: String,
        slots: Vec<BinderSlot>,
    },
    Named {
        field: String,
        slots: BTreeMap<String, BinderSlot>,
    },
    Single {
        field: String,
        slot: BinderSlot,
    },
}

One adapter-declared binding shape for one op-template field.

Three variants cover the common protocol shapes. The field names the op-template field this binder describes — surfaced in error diagnostics so the operator can locate the slot quickly.

Variants

Positional

Positional binding (slot index = position in vec).

Example: a CQL prepared statement with three ? placeholders → three positional slots. The slot at index 0 binds to the first ?, etc.

Fields

field: String

The op-template field bound.

slots: Vec<BinderSlot>

One slot per placeholder, in position order.

Named

Named binding (slot key = parameter name).

Example: a CQL prepared statement with :id / :val named parameters → two named slots keyed by id / val. BTreeMap for deterministic diagnostic ordering.

Fields

field: String

The op-template field bound.

slots: BTreeMap<String, BinderSlot>

One slot per named parameter.

Single

Single-value binding (the whole field IS one typed value).

Example: an HTTP body bound as one JSON object, an MQTT payload bound as Bytes. The slot supplies the field’s entire value with the lvalue type declared by the protocol.

Fields

field: String

The op-template field bound.

slot: BinderSlot

The slot supplying the field’s whole value.

Implementations

impl Binder

pub fn field(&self) -> &str

Op-template field this binder describes.

pub fn slots(&self) -> Vec<(String, &BinderSlot)>

Walk every slot in this binder for verification or codegen. Yields (slot_label, slot) pairs where slot_label is a human-readable position hint ("[0]" for positional, ":name" for named, "" for single).

Trait Implementations

impl Clone for Binder

fn clone(&self) -> Binder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Binder

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

Formats the value using the given formatter.