Returns the key of the tag attribute that distinguishes structures of this
Form; returns undefined if this Form has no distinguishing tag
attribute. Used to accelerate discrimination of polymorphic structural
types with nominal type hints.
Readonlyunit
unit:T
Returns a default–possibly undefined–value of type T. Used as the
fallback return value when [Item.coerce coercing] an invalid structural
value.
Methods
Abstractcast
cast(item, object?): T
Converts a structurally typed item into a nominally typed JavaScript
object, optionally based on the provided prototype object.
Transformation between a structurally typed [Item] and a nominally typed JavaScript object.