Engine

Defined in: packages/core/src/engine/index.ts:131

The engine is used to parse rules and evaluate expressions. It is the main entry point to the publicodes library.

Type Parameters

Type Parameter	Default type	Description
`RuleNames` extends `string`	`string`	All rules names. Allows to automatically autocomplete rules names in the engine when using Engine.getRule or Engine.setSituation

Constructors

new Engine()

new Engine<RuleNames>(rules, options): Engine<RuleNames>

Defined in: packages/core/src/engine/index.ts:150

Creates an evaluation engine with the publicode rules given as arguments.

Parameters

Parameter	Type	Description
`rules`	\| `ParsedRules`<`RuleNames`> \| `Partial`<`Record`<`RuleNames`, `RawRule`>>	The publicodes model to use (RawPublicodes or ParsedRules)
`options`	`EngineOptions`	Configuration options

Returns

Engine<RuleNames>

Methods

evaluate()

evaluate(value): EvaluatedNode

Defined in: packages/core/src/engine/index.ts:407

Evaluate a publicodes expression.

Use the current situation set by setSituation.

Parameters

Parameter	Type	Description
`value`	\| `ASTNode` \| `PublicodesExpression`	The publicodes expression to evaluate.

Returns

EvaluatedNode

The ASTNode of the publicodes expression decorated with evaluation results (nodeValue, unit, missingVariables, etc.)

Remarks

To improve performance, the engine will cache the evaluation of the expression, and all its byproducts (intermediate evaluations). The cache is reset when the situation is updated with setSituation. You can also manually reset it with resetCache.

getParsedRules()

getParsedRules(): ParsedRules<RuleNames>

Defined in: packages/core/src/engine/index.ts:331

Returns

ParsedRules<RuleNames>

the parsed rules used by the engine

Remarks

The private rules are not included in the parsed rules

getPossibilitiesFor()

getPossibilitiesFor(dottedName, options): null | Possibility[]

Defined in: packages/core/src/engine/index.ts:368

Retrieves the list of possible values for a given rule.

Parameters

Parameter	Type	Description
`dottedName`	`RuleNames`	The dotted name of the rule to get possibilities for
`options`	{ `filterNotApplicable`: `boolean`; }	Options object
`options.filterNotApplicable`?	`boolean`	When true, filters out possibilities that are not applicable based on the current situation. Defaults to false.

Returns

null | Possibility[]

Array of possibility nodes if the rule has possibilities defined, null otherwise

Example

Publicodes

contrat:
 une possibilité:
  - "'CDI'"
  - "'CDD'"
```js
engine.getPossibilitiesFor('contrat')

getRule()

getRule(dottedName): RuleNode

Defined in: packages/core/src/engine/index.ts:305

Get the rule with the given dottedName.

Parameters

Parameter	Type
`dottedName`	`RuleNames`

Returns

RuleNode

Throws

PublicodesError if the rule does not exist or is private

getSituation()

getSituation(): Partial<Record<RuleNames, 
  | ASTNode
| PublicodesExpression>>

Defined in: packages/core/src/engine/index.ts:344

Retrieve the current situation used for the evaluation

This situation can be slightly different from the one set with setSituation if some values were filtered out because of evaluation errors.

Returns

Partial<Record<RuleNames, | ASTNode | PublicodesExpression>>

Situation used by the engine

inversionFail()

inversionFail(): boolean

Defined in: packages/core/src/engine/index.ts:295

Returns

boolean

true if the engine has encountered an inversion error during the last evaluation

resetCache()

resetCache(): void

Defined in: packages/core/src/engine/index.ts:193

Reset the engine cache. This will clear all the cached evaluations.

Returns

void

setSituation()

setSituation(situation, options): Engine<RuleNames>

Defined in: packages/core/src/engine/index.ts:204

Set the situation used for the evaluation.

All subsequent evaluations will use this situation. Reset the evaluation cache to avoid inconsistencies, so it is costly to call this method frequently with the same situation.

Parameters

Parameter	Type	Description
`situation`	`Partial`<`Record`<`RuleNames`, \| `ASTNode` \| `PublicodesExpression`>>	The situation to set (see Situation)
`options`	{ `keepPreviousSituation`: `boolean`; `strict`: `boolean`; }	-
`options.keepPreviousSituation`?	`boolean`	If true, the previous situation is kept and the new values are added to it. Default `false`
`options.strict`?	`boolean`	If set to true, the engine will throw when the situation contains invalid values (rules that don’t exists, or values with syntax errors). If set to false, it will log the error and filter the invalid values from the situation Overrides the EngineOptions strict option

Returns

Engine<RuleNames>

shallowCopy()

shallowCopy(): Engine<RuleNames>

Defined in: packages/core/src/engine/index.ts:485

Shallow Engine instance copy. Useful to evaluate the same rules with different situations.

Returns

Engine<RuleNames>

a new Engine instance with the same baseContext, context, publicParsedRules, publicSituation and cache attributes.