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JavaScript@langchain/corelanguage_modelsstreamUsageMetadataStreamthen

Method●Since v1.1

then

Copy

then<
  TResult1 = UsageMetadata | undefined,
  TResult2 = never
>(
  onfulfilled: (value: UsageMetadata

View source on GitHub

|

undefined

)

=

>

TResult1

|

PromiseLike

<

TResult1

>

|

null

,

onrejected

:

(

reason

:

unknown

)

=

>

TResult2

|

PromiseLike

<

TResult2

>

|

null

)

:

PromiseLike

<

TResult1

|

TResult2

>

Parameters

Name	Type	Description
`onfulfilled`	`(value: UsageMetadata \| undefined) => TResult1 \| PromiseLike<TResult1> \| null`
`onrejected`	`(reason: unknown) => TResult2 \| PromiseLike<TResult2> \| null`

Attaches callbacks for the resolution and/or rejection of the Promise.

The callback to execute when the Promise is resolved.

The callback to execute when the Promise is rejected.