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*   [Get started](/v0.1/docs/get_started/)
    
    *   [Introduction](/v0.1/docs/get_started/introduction/)
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*   [Modules](/v0.1/docs/modules/)
    
    *   [Model I/O](/v0.1/docs/modules/model_io/)
        
        *   [Quickstart](/v0.1/docs/modules/model_io/quick_start/)
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        *   [Model I/O](/v0.1/docs/modules/model_io/)
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            *   [Quick Start](/v0.1/docs/modules/model_io/output_parsers/quick_start/)
            *   [Custom output parsers](/v0.1/docs/modules/model_io/output_parsers/custom/)
            *   [Output Parser Types](/v0.1/docs/modules/model_io/output_parsers/types/)
                
                *   [String output parser](/v0.1/docs/modules/model_io/output_parsers/types/string/)
                *   [HTTP Response Output Parser](/v0.1/docs/modules/model_io/output_parsers/types/http_response/)
                *   [JSON Output Functions Parser](/v0.1/docs/modules/model_io/output_parsers/types/json_functions/)
                *   [Bytes output parser](/v0.1/docs/modules/model_io/output_parsers/types/bytes/)
                *   [Combining output parsers](/v0.1/docs/modules/model_io/output_parsers/types/combining_output_parser/)
                *   [List parser](/v0.1/docs/modules/model_io/output_parsers/types/csv/)
                *   [Custom list parser](/v0.1/docs/modules/model_io/output_parsers/types/custom_list_parser/)
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                *   [Structured output parser](/v0.1/docs/modules/model_io/output_parsers/types/structured/)
                *   [XML output parser](/v0.1/docs/modules/model_io/output_parsers/types/xml/)
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*   [](/v0.1/)
*   [Modules](/v0.1/docs/modules/)
*   [Model I/O](/v0.1/docs/modules/model_io/)
*   [Output Parsers](/v0.1/docs/modules/model_io/output_parsers/)
*   [Output Parser Types](/v0.1/docs/modules/model_io/output_parsers/types/)
*   List parser

List parser
===========

This output parser can be used when you want to return a list of comma-separated items.

tip

See [this section for general instructions on installing integration packages](/v0.1/docs/get_started/installation/#installing-integration-packages).

*   npm
*   Yarn
*   pnpm

    npm install @langchain/openai

    yarn add @langchain/openai

    pnpm add @langchain/openai

    import { OpenAI } from "@langchain/openai";import { PromptTemplate } from "@langchain/core/prompts";import { CommaSeparatedListOutputParser } from "@langchain/core/output_parsers";import { RunnableSequence } from "@langchain/core/runnables";export const run = async () => {  // With a `CommaSeparatedListOutputParser`, we can parse a comma separated list.  const parser = new CommaSeparatedListOutputParser();  const chain = RunnableSequence.from([    PromptTemplate.fromTemplate("List five {subject}.\n{format_instructions}"),    new OpenAI({ temperature: 0 }),    parser,  ]);  /*   List five ice cream flavors.   Your response should be a list of comma separated values, eg: `foo, bar, baz`  */  const response = await chain.invoke({    subject: "ice cream flavors",    format_instructions: parser.getFormatInstructions(),  });  console.log(response);  /*			[			'Vanilla',			'Chocolate',			'Strawberry',			'Mint Chocolate Chip',			'Cookies and Cream'			]		*/};

#### API Reference:

*   [OpenAI](https://api.js.langchain.com/classes/langchain_openai.OpenAI.html) from `@langchain/openai`
*   [PromptTemplate](https://api.js.langchain.com/classes/langchain_core_prompts.PromptTemplate.html) from `@langchain/core/prompts`
*   [CommaSeparatedListOutputParser](https://api.js.langchain.com/classes/langchain_core_output_parsers.CommaSeparatedListOutputParser.html) from `@langchain/core/output_parsers`
*   [RunnableSequence](https://api.js.langchain.com/classes/langchain_core_runnables.RunnableSequence.html) from `@langchain/core/runnables`

* * *

#### Help us out by providing feedback on this documentation page:

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