Struct SignatureBuilder 

pub struct SignatureBuilder { /* private fields */ }

Builder for constructing a Signature.

Enforces that the signature has at least one input and one output field at build time.

Implementations

impl SignatureBuilder

pub fn input(self, def: FieldDef) -> Self

Add an input field. The field’s kind is set to FieldKind::Input regardless of what was passed.

pub fn output(self, def: FieldDef) -> Self

Add an output field. The field’s kind is set to FieldKind::Output regardless of what was passed.

pub fn build(self) -> Result<Signature>

Validate and build the signature.

Validation covers: at-least-one input + at-least-one output (existing); structural validation of every transitively-reachable FieldType::OneOf and FieldType::AnyOf field (new) — non-empty arms, discriminator parallelism with arms, unique tag values, and arm-shape consistency with the named discriminator property.

Schema-conversion-driven construction (via field_type_from_schema in typesayer) is validated at conversion time and would not produce malformed variants here. The validation in this builder is the safety net for callers that construct FieldType::OneOf / AnyOf programmatically.

Errors

Returns PredictError::InvalidSignature if there are no input or output fields, or if any variant field violates the structural constraints above.