Struct StructuredOutputParser 

pub struct StructuredOutputParser { /* private fields */ }

结构化输出解析器

将 LLM 输出的键值对格式（每行一个 key: value）解析为 HashMap。 适用于 LLM 以非 JSON 格式输出结构化信息的场景。

格式

输入格式应为每行一个 key: value，例如：

姓名: 张三
年龄: 28
城市: 北京

示例

use langchainrust::output_parsers::StructuredOutputParser;

let parser = StructuredOutputParser::new();
let result = parser.parse("姓名: 张三\n年龄: 28").await?;
assert_eq!(result.get("姓名").unwrap(), "张三");

Implementations

impl StructuredOutputParser

pub fn new() -> Self

pub fn with_separator(separator: char) -> Self

使用自定义分隔符创建解析器

Trait Implementations

impl BaseOutputParser<HashMap<String, String>> for StructuredOutputParser

fn parse<'life0, 'life1, 'async_trait>( &'life0 self, text: &'life1 str, ) -> Pin<Box<dyn Future<Output = OutputParserResult<HashMap<String, String>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

将原始 LLM 输出文本解析为目标类型

fn get_format_instructions(&self) -> String

获取格式指令（用于提示 LLM 按指定格式输出）

fn parse_with_retry<'life0, 'life1, 'async_trait>( &'life0 self, text: &'life1 str, max_retries: usize, ) -> Pin<Box<dyn Future<Output = OutputParserResult<Output>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

带重试的解析（默认实现：真正重试 max_retries 次）

impl Default for StructuredOutputParser

fn default() -> Self

Returns the “default value” for a type.

impl Runnable<String, HashMap<String, String>> for StructuredOutputParser

type Error = OutputParserError

Error type.

fn invoke<'life0, 'async_trait>( &'life0 self, input: String, _config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<HashMap<String, String>, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Transforms single input to output.

fn stream<'life0, 'async_trait>( &'life0 self, input: String, _config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<Pin<Box<dyn Stream<Item = Result<HashMap<String, String>, Self::Error>> + Send>>, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Streaming output - for real-time responses (LLM, etc).

fn batch<'life0, 'async_trait>( &'life0 self, inputs: Vec<Input>, config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<Vec<Output>, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Batch processing - transforms multiple inputs to outputs.

fn transform<'life0, 'async_trait>( &'life0 self, input: Pin<Box<dyn Stream<Item = Result<Input, Self::Error>> + Send>>, config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<Pin<Box<dyn Stream<Item = Result<Output, Self::Error>> + Send>>, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Stream-to-stream transformation - the core of LCEL streaming.