predicate.define · Umwelt docs

Reference/Commands/predicate.define

predicate.definecommandsince 0.1

Declares a predicate before claims use it: what its object is, and how many values a subject may have.

Command lineTypeScript.NET

Request

umwelt call story.umw predicate.define '{
  "projectId": "ball",
  "predicate": {
    "id": "stole",
    "label": "stole",
    "object": "entity",
    "cardinality": "many"
  }
}'

Request

const result = await client.predicateDefine({
  projectId: 'ball',
  predicate: { id: 'stole', label: 'stole', object: 'entity', cardinality: 'many' },
});

Request

var result = engine.PredicateDefine(new DefinePredicateInput
{
    ProjectId = "ball",
    Predicate = new PredicateDef
    {
        Id = "stole",
        Label = "stole",
        Object = ObjectKind.Entity,
        Cardinality = Cardinality.Many,
    },
});

Response

{
  "id": "stole",
  "label": "stole",
  "object": "entity",
  "cardinality": "many"
}

Payload

Field	Type	Description
`projectId`required	string	The project to write to.
`predicate`required	PredicateDef	The predicate: `id`, `label`, `object` (`entity`, `value` or `none`), `cardinality` (`one` or `many`) and optionally `subjectTypes`.

Result

Field	Type	Description
`id`always	string	The predicate’s id. Ids beginning with `umwelt:` are reserved.
`label`always	string	How it reads.
`object`always	"entity" \| "value" \| "none"	What its object is: an `entity`, a `value`, or `none`.
`cardinality`always	"one" \| "many"	`one` makes it functional: one value per subject at a time. `many` allows several.
`subjectTypes`	string[]	The entity types its subject may have. Absent: any.

Rules

Cardinality one is functional. A subject has one value at a time, so two values in the same slot are a contradiction (contradictions, check.utterance).

Reserved predicates. Ids beginning with umwelt: are built in: umwelt:member-of, umwelt:name, umwelt:title, umwelt:alias, umwelt:holds.

Defining it again is a no-op. The same definition returns it unchanged; a different one is a CONFLICT.

Errors

VALIDATION_FAILEDThe payload is malformed, or the id begins with umwelt:.

CONFLICTThe predicate exists with another definition. details.predicate has the stored one.

NOT_FOUNDThe project does not exist.

HANDSHAKE_REQUIREDOver the protocol, hello was not sent first.

Every code is listed in Errors.

Payload

Result

Rules

Errors

See also