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JavaScript@langchain/langgraphwebStateSchemaFieldsToStateDefinition
Type●Since v1.3

StateSchemaFieldsToStateDefinition

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StateSchemaFieldsToStateDefinition: { [K in keyof TFields]: StateSchemaFieldToChannel<TFields[K]> }
View source on GitHub

Converts StateSchema fields into a strongly-typed State Definition object, where each field is mapped to its channel type.

This utility type is used internally to create the shape of the state channels for a given schema, substituting each field with the result of StateSchemaFieldToChannel.

If you define a state schema as:

const fields = {
  a: ReducedValue<number, string>(),
  b: UntrackedValue<boolean>(),
  c: SomeSerializableSchemaType, // SerializableSchema<in, out>
}

then StateSchemaFieldsToStateDefinition<typeof fields> yields:

{
  a: BaseChannel<number, string>;
  b: BaseChannel<boolean, boolean>;
  c: BaseChannel<typeof schema's output type, typeof schema's input type>;
}