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JavaScript@langchain/langgraphpregelChannelwriteTo
Method●Since v0.3

writeTo

Creates a ChannelWrite that specifies how to write values to channels. This is used to define how nodes send output to channels.

Copy
writeTo(channels: string[], writes: Record<string, unknown>): ChannelWrite

Parameters

NameTypeDescription
channels*string[]

Array of channel names to write to

writesRecord<string, unknown>

Optional map of channel names to values or transformations

Example

Copy
// Write to multiple channels
const write = Channel.writeTo(["output", "state"]);

// Write with specific values
const write = Channel.writeTo(["output"], {
  state: "completed",
  result: calculateResult()
});

// Write with a transformation function
const write = Channel.writeTo(["output"], {
  result: (x) => processResult(x)
});
View source on GitHub