createExpressionValidator()
createExpressionValidator(
functionMeta?:ExpressionFunctionMetaRegistry):QueryValidator
Defined in: expr/src/utils/createExpressionValidator.ts:29
Configure-once factory returning a QueryValidator that flags rules whose lhs/rhs
expressions are invalid — unknown function, arity mismatch, or empty field reference —
checked against functionMeta merged over the built-in defaultFunctionMeta (the
same merge QueryBuilderExpressions applies, so one metadata registry drives the UI and
validation alike).
The returned validator produces a sparse ValidationMap: only invalid,
expression-bearing rules get an entry ({ valid: false, reasons }), keyed by rule.id.
Rules without expressions, valid rules, and rules lacking an id are omitted and thus
treated as valid. Validation is format-agnostic — it does not check per-format
serializers; the rule processors handle serializer presence per export format.
Pass the result as formatQuery's validator option to annotate format: 'diagnostics'
output and to skip invalid rules from standard exports, or to a <QueryBuilder>'s
validator prop for live in-UI feedback.
Parameters
| Parameter | Type |
|---|---|
functionMeta? | ExpressionFunctionMetaRegistry |
Returns
API documentation is generated from the latest commit on the main branch. It may be somewhat inconsistent with official releases of React Query Builder.