Copyright	(c) 2025 Tushar Adhatrao
License	MIT
Maintainer	Tushar Adhatrao <tusharadhatrao@gmail.com>
Stability	experimental
Safe Haskell	Safe-Inferred
Language	Haskell2010

Langchain.Memory.Core

Description

Implementation of LangChain's memory management patterns, providing:

Chat history tracking with size limits
Message addition/trimming strategies
Integration with Runnable workflows

Example usage:

-- Create memory with 5-message window
memory = WindowBufferMemory 5 (initialChatMessage "You are an assistant")

-- Add user message
newMemory <- addUserMessage memory "Hello, world!"

-- Retrieve current messages
messages <- messages newMemory
-- Right [Message System "...", Message User "Hello, world!"]

Synopsis

class BaseMemory m where
- messages :: m -> IO (Either String ChatMessage)
- addUserMessage :: m -> Text -> IO (Either String m)
- addAiMessage :: m -> Text -> IO (Either String m)
- addMessage :: m -> Message -> IO (Either String m)
- clear :: m -> IO (Either String m)
data WindowBufferMemory = WindowBufferMemory {
- maxWindowSize :: Int
- windowBufferMessages :: ChatMessage
}
trimChatMessage :: Int -> ChatMessage -> ChatMessage
addAndTrim :: Int -> Message -> ChatMessage -> ChatMessage
initialChatMessage :: Text -> ChatMessage

Documentation

class BaseMemory m where Source #

Base typeclass for memory implementations Defines standard operations for chat history management.

Example instance:

instance BaseMemory MyMemory where
  messages = ...
  addUserMessage = ...

Methods

messages :: m -> IO (Either String ChatMessage) Source #

Retrieve current chat history

addUserMessage :: m -> Text -> IO (Either String m) Source #

Add user message to history

addAiMessage :: m -> Text -> IO (Either String m) Source #

Add AI response to history

addMessage :: m -> Message -> IO (Either String m) Source #

Add generic message to history

clear :: m -> IO (Either String m) Source #

Reset memory to initial state

Instances

Instances details

BaseMemory WindowBufferMemory Source #

Instance details

Defined in Langchain.Memory.Core

Methods

messages :: WindowBufferMemory -> IO (Either String ChatMessage) Source #

addUserMessage :: WindowBufferMemory -> Text -> IO (Either String WindowBufferMemory) Source #

addAiMessage :: WindowBufferMemory -> Text -> IO (Either String WindowBufferMemory) Source #

addMessage :: WindowBufferMemory -> Message -> IO (Either String WindowBufferMemory) Source #

clear :: WindowBufferMemory -> IO (Either String WindowBufferMemory) Source #

data WindowBufferMemory Source #

Sliding window memory implementation. Stores chat history with maximum size limit.

Example:

>>> let mem = WindowBufferMemory 2 (NE.singleton (Message System "Sys" defaultMessageData))
>>> addMessage mem (Message User "Hello" defaultMessageData)
Right (WindowBufferMemory {maxWindowSize = 2, ...})

Constructors

WindowBufferMemory
Fields maxWindowSize :: Int Maximum number of messages to retain windowBufferMessages :: ChatMessage Current message buffer [[9]]

Instances

Instances details

Show WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core Methods showsPrec :: Int -> WindowBufferMemory -> ShowS # show :: WindowBufferMemory -> String # showList :: [WindowBufferMemory] -> ShowS #
Eq WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core Methods (==) :: WindowBufferMemory -> WindowBufferMemory -> Bool # (/=) :: WindowBufferMemory -> WindowBufferMemory -> Bool #
BaseMemory WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core Methods messages :: WindowBufferMemory -> IO (Either String ChatMessage) Source # addUserMessage :: WindowBufferMemory -> Text -> IO (Either String WindowBufferMemory) Source # addAiMessage :: WindowBufferMemory -> Text -> IO (Either String WindowBufferMemory) Source # addMessage :: WindowBufferMemory -> Message -> IO (Either String WindowBufferMemory) Source # clear :: WindowBufferMemory -> IO (Either String WindowBufferMemory) Source #
Runnable WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core Associated Types type RunnableInput WindowBufferMemory Source # type RunnableOutput WindowBufferMemory Source # Methods invoke :: WindowBufferMemory -> RunnableInput WindowBufferMemory -> IO (Either String (RunnableOutput WindowBufferMemory)) Source # batch :: WindowBufferMemory -> [RunnableInput WindowBufferMemory] -> IO (Either String [RunnableOutput WindowBufferMemory]) Source # stream :: WindowBufferMemory -> RunnableInput WindowBufferMemory -> (RunnableOutput WindowBufferMemory -> IO ()) -> IO (Either String ()) Source #
type RunnableInput WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core type RunnableInput WindowBufferMemory = Text
type RunnableOutput WindowBufferMemory Source #
Instance details Defined in Langchain.Memory.Core type RunnableOutput WindowBufferMemory = WindowBufferMemory

trimChatMessage :: Int -> ChatMessage -> ChatMessage Source #

Trim chat history to last n messages Example:

>>> let msgs = NE.fromList [msg1, msg2, msg3]
>>> trimChatMessage 2 msgs
[msg2, msg3]

addAndTrim :: Int -> Message -> ChatMessage -> ChatMessage Source #

Add and maintain window size Example:

>>> let msgs = NE.fromList [msg1]
>>> addAndTrim 2 msg2 msgs
[msg1, msg2]

initialChatMessage :: Text -> ChatMessage Source #

Create initial chat history Example:

>>> initialChatMessage "You are Qwen"
[Message System "You are Qwen"]