Deterministic operators

Hierarchy

Build a deterministic single-parent forest.

Hierarchy is the single-parent deterministic mirror of SemHierarchy.

Worked example

Hierarchy(
    name="build-folder-hierarchy",
    input_spaces=("folders",),
    output_space="folder-hierarchy",
    primary_key="path",
    fn=lambda parent, child: (
        child["path"].startswith(parent["path"] + "/")
    ),
)

Callable contract

fn(parent, child) -> bool. True means the first value is broader than the second. The resulting transitive reduction must give every value at most one immediate parent; conflicting deterministic parents fail explicitly.

Rows available to the callable

Each row argument contains the declared primary-key fields and the declared evidence fields available for that input role. If the callable reads a field that is not part of the primary key, declare it as evidence.

Parameter	Default	Meaning
`input_spaces`	required	The Space or Spaces read by the task.
`output_space`	required	The Space that receives the task output.
`name`	required	A stable task name used in sessions, reviews, and metrics.
`primary_key`	id	The field, or tuple of fields, that identifies one task input. Duplicate primary-key values are evaluated once.
`evidence`	none	Optional fields made available to the callable in addition to the primary key.
`fn`	required	A deterministic callable that completely defines the operation's decision. Use an importable named function from your package, or PythonFunction(name=..., source=...) when authoring through the hosted API or node editor. Pairwise endomorphic functions may declare an exact indexed candidate_gate.
`function_parameters`	registered defaults	Typed values bound to parameters declared by the registered function. Finite candidate sets let reviewed evidence support parameter advice.

Output

A forest with parent, child, root, and ancestor relationships.

Design guidance

Use Hierarchy when an exact rule defines one parent chain. Use Taxonomy when exact multi-parent ancestry is valid, and SemHierarchy when ancestry requires interpretation.