@langchain/core/dist/runnables/branch.cjs.map

Core LangChain.js abstractions and schemas

{"version":3,"file":"branch.cjs","names":["Runnable","fields: {\n    branches: Branch<RunInput, RunOutput>[];\n    default: Runnable<RunInput, RunOutput>;\n  }","branches: [\n      ...BranchLike<RunInput, RunOutput>[],\n      RunnableLike<RunInput, RunOutput>\n    ]","coercedBranches: Branch<RunInput, RunOutput>[]","_coerceToRunnable","input: RunInput","config?: Partial<RunnableConfig>","runManager?: CallbackManagerForChainRun","patchConfig","config: RunnableConfig","getCallbackManagerForConfig","_coerceToDict","concat"],"sources":["../../src/runnables/branch.ts"],"sourcesContent":["import {\n  Runnable,\n  RunnableLike,\n  _coerceToDict,\n  _coerceToRunnable,\n} from \"./base.js\";\nimport {\n  RunnableConfig,\n  getCallbackManagerForConfig,\n  patchConfig,\n} from \"./config.js\";\nimport { CallbackManagerForChainRun } from \"../callbacks/manager.js\";\nimport { concat } from \"../utils/stream.js\";\n\n/**\n * Type for a branch in the RunnableBranch. It consists of a condition\n * runnable and a branch runnable. The condition runnable is used to\n * determine whether the branch should be executed, and the branch runnable\n * is executed if the condition is true.\n */\nexport type Branch<RunInput, RunOutput> = [\n  Runnable<RunInput, boolean>,\n  Runnable<RunInput, RunOutput>\n];\n\nexport type BranchLike<RunInput, RunOutput> = [\n  RunnableLike<RunInput, boolean>,\n  RunnableLike<RunInput, RunOutput>\n];\n\n/**\n * Class that represents a runnable branch. The RunnableBranch is\n * initialized with an array of branches and a default branch. When invoked,\n * it evaluates the condition of each branch in order and executes the\n * corresponding branch if the condition is true. If none of the conditions\n * are true, it executes the default branch.\n * @example\n * ```typescript\n * const branch = RunnableBranch.from([\n *   [\n *     (x: { topic: string; question: string }) =>\n *       x.topic.toLowerCase().includes(\"anthropic\"),\n *     anthropicChain,\n *   ],\n *   [\n *     (x: { topic: string; question: string }) =>\n *       x.topic.toLowerCase().includes(\"langchain\"),\n *     langChainChain,\n *   ],\n *   generalChain,\n * ]);\n *\n * const fullChain = RunnableSequence.from([\n *   {\n *     topic: classificationChain,\n *     question: (input: { question: string }) => input.question,\n *   },\n *   branch,\n * ]);\n *\n * const result = await fullChain.invoke({\n *   question: \"how do I use LangChain?\",\n * });\n * ```\n */\n// eslint-disable-next-line @typescript-eslint/no-explicit-any\nexport class RunnableBranch<RunInput = any, RunOutput = any> extends Runnable<\n  RunInput,\n  RunOutput\n> {\n  static lc_name() {\n    return \"RunnableBranch\";\n  }\n\n  lc_namespace = [\"langchain_core\", \"runnables\"];\n\n  lc_serializable = true;\n\n  default: Runnable<RunInput, RunOutput>;\n\n  branches: Branch<RunInput, RunOutput>[];\n\n  constructor(fields: {\n    branches: Branch<RunInput, RunOutput>[];\n    default: Runnable<RunInput, RunOutput>;\n  }) {\n    super(fields);\n    this.branches = fields.branches;\n    this.default = fields.default;\n  }\n\n  /**\n   * Convenience method for instantiating a RunnableBranch from\n   * RunnableLikes (objects, functions, or Runnables).\n   *\n   * Each item in the input except for the last one should be a\n   * tuple with two items. The first is a \"condition\" RunnableLike that\n   * returns \"true\" if the second RunnableLike in the tuple should run.\n   *\n   * The final item in the input should be a RunnableLike that acts as a\n   * default branch if no other branches match.\n   *\n   * @example\n   * ```ts\n   * import { RunnableBranch } from \"@langchain/core/runnables\";\n   *\n   * const branch = RunnableBranch.from([\n   *   [(x: number) => x > 0, (x: number) => x + 1],\n   *   [(x: number) => x < 0, (x: number) => x - 1],\n   *   (x: number) => x\n   * ]);\n   * ```\n   * @param branches An array where the every item except the last is a tuple of [condition, runnable]\n   *   pairs. The last item is a default runnable which is invoked if no other condition matches.\n   * @returns A new RunnableBranch.\n   */\n  // eslint-disable-next-line @typescript-eslint/no-explicit-any\n  static from<RunInput = any, RunOutput = any>(\n    branches: [\n      ...BranchLike<RunInput, RunOutput>[],\n      RunnableLike<RunInput, RunOutput>\n    ]\n  ) {\n    if (branches.length < 1) {\n      throw new Error(\"RunnableBranch requires at least one branch\");\n    }\n    const branchLikes = branches.slice(0, -1) as BranchLike<\n      RunInput,\n      RunOutput\n    >[];\n    const coercedBranches: Branch<RunInput, RunOutput>[] = branchLikes.map(\n      ([condition, runnable]) => [\n        _coerceToRunnable(condition),\n        _coerceToRunnable(runnable),\n      ]\n    );\n    const defaultBranch = _coerceToRunnable(\n      branches[branches.length - 1] as RunnableLike<RunInput, RunOutput>\n    );\n    return new this({\n      branches: coercedBranches,\n      default: defaultBranch,\n    });\n  }\n\n  async _invoke(\n    input: RunInput,\n    config?: Partial<RunnableConfig>,\n    runManager?: CallbackManagerForChainRun\n  ): Promise<RunOutput> {\n    let result;\n    for (let i = 0; i < this.branches.length; i += 1) {\n      const [condition, branchRunnable] = this.branches[i];\n      const conditionValue = await condition.invoke(\n        input,\n        patchConfig(config, {\n          callbacks: runManager?.getChild(`condition:${i + 1}`),\n        })\n      );\n      if (conditionValue) {\n        result = await branchRunnable.invoke(\n          input,\n          patchConfig(config, {\n            callbacks: runManager?.getChild(`branch:${i + 1}`),\n          })\n        );\n        break;\n      }\n    }\n    if (!result) {\n      result = await this.default.invoke(\n        input,\n        patchConfig(config, {\n          callbacks: runManager?.getChild(\"branch:default\"),\n        })\n      );\n    }\n    return result;\n  }\n\n  async invoke(\n    input: RunInput,\n    config: RunnableConfig = {}\n  ): Promise<RunOutput> {\n    return this._callWithConfig(this._invoke, input, config);\n  }\n\n  async *_streamIterator(input: RunInput, config?: Partial<RunnableConfig>) {\n    const callbackManager_ = await getCallbackManagerForConfig(config);\n    const runManager = await callbackManager_?.handleChainStart(\n      this.toJSON(),\n      _coerceToDict(input, \"input\"),\n      config?.runId,\n      undefined,\n      undefined,\n      undefined,\n      config?.runName\n    );\n    let finalOutput;\n    let finalOutputSupported = true;\n    let stream;\n    try {\n      for (let i = 0; i < this.branches.length; i += 1) {\n        const [condition, branchRunnable] = this.branches[i];\n        const conditionValue = await condition.invoke(\n          input,\n          patchConfig(config, {\n            callbacks: runManager?.getChild(`condition:${i + 1}`),\n          })\n        );\n        if (conditionValue) {\n          stream = await branchRunnable.stream(\n            input,\n            patchConfig(config, {\n              callbacks: runManager?.getChild(`branch:${i + 1}`),\n            })\n          );\n          for await (const chunk of stream) {\n            yield chunk;\n            if (finalOutputSupported) {\n              if (finalOutput === undefined) {\n                finalOutput = chunk;\n              } else {\n                try {\n                  finalOutput = concat(finalOutput, chunk);\n                } catch {\n                  finalOutput = undefined;\n                  finalOutputSupported = false;\n                }\n              }\n            }\n          }\n          break;\n        }\n      }\n      if (stream === undefined) {\n        stream = await this.default.stream(\n          input,\n          patchConfig(config, {\n            callbacks: runManager?.getChild(\"branch:default\"),\n          })\n        );\n        for await (const chunk of stream) {\n          yield chunk;\n          if (finalOutputSupported) {\n            if (finalOutput === undefined) {\n              finalOutput = chunk;\n            } else {\n              try {\n                finalOutput = concat(finalOutput, chunk as RunOutput);\n              } catch {\n                finalOutput = undefined;\n                finalOutputSupported = false;\n              }\n            }\n          }\n        }\n      }\n    } catch (e) {\n      await runManager?.handleChainError(e);\n      throw e;\n    }\n    await runManager?.handleChainEnd(finalOutput ?? {});\n  }\n}\n"],"mappings":";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;AAkEA,IAAa,iBAAb,cAAqEA,sBAGnE;CACA,OAAO,UAAU;AACf,SAAO;CACR;CAED,eAAe,CAAC,kBAAkB,WAAY;CAE9C,kBAAkB;CAElB;CAEA;CAEA,YAAYC,QAGT;EACD,MAAM,OAAO;EACb,KAAK,WAAW,OAAO;EACvB,KAAK,UAAU,OAAO;CACvB;;;;;;;;;;;;;;;;;;;;;;;;;;CA4BD,OAAO,KACLC,UAIA;AACA,MAAI,SAAS,SAAS,EACpB,OAAM,IAAI,MAAM;EAElB,MAAM,cAAc,SAAS,MAAM,GAAG,GAAG;EAIzC,MAAMC,kBAAiD,YAAY,IACjE,CAAC,CAAC,WAAW,SAAS,KAAK,CACzBC,+BAAkB,UAAU,EAC5BA,+BAAkB,SAAS,AAC5B,EACF;EACD,MAAM,gBAAgBA,+BACpB,SAAS,SAAS,SAAS,GAC5B;AACD,SAAO,IAAI,KAAK;GACd,UAAU;GACV,SAAS;EACV;CACF;CAED,MAAM,QACJC,OACAC,QACAC,YACoB;EACpB,IAAI;AACJ,OAAK,IAAI,IAAI,GAAG,IAAI,KAAK,SAAS,QAAQ,KAAK,GAAG;GAChD,MAAM,CAAC,WAAW,eAAe,GAAG,KAAK,SAAS;GAClD,MAAM,iBAAiB,MAAM,UAAU,OACrC,OACAC,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,CAAC,UAAU,EAAE,IAAI,GAAG,CAAC,CACtD,EAAC,CACH;AACD,OAAI,gBAAgB;IAClB,SAAS,MAAM,eAAe,OAC5B,OACAA,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,CAAC,OAAO,EAAE,IAAI,GAAG,CAAC,CACnD,EAAC,CACH;AACD;GACD;EACF;AACD,MAAI,CAAC,QACH,SAAS,MAAM,KAAK,QAAQ,OAC1B,OACAA,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,iBAAiB,CAClD,EAAC,CACH;AAEH,SAAO;CACR;CAED,MAAM,OACJH,OACAI,SAAyB,CAAE,GACP;AACpB,SAAO,KAAK,gBAAgB,KAAK,SAAS,OAAO,OAAO;CACzD;CAED,OAAO,gBAAgBJ,OAAiBC,QAAkC;EACxE,MAAM,mBAAmB,MAAMI,2CAA4B,OAAO;EAClE,MAAM,aAAa,MAAM,kBAAkB,iBACzC,KAAK,QAAQ,EACbC,2BAAc,OAAO,QAAQ,EAC7B,QAAQ,OACR,QACA,QACA,QACA,QAAQ,QACT;EACD,IAAI;EACJ,IAAI,uBAAuB;EAC3B,IAAI;AACJ,MAAI;AACF,QAAK,IAAI,IAAI,GAAG,IAAI,KAAK,SAAS,QAAQ,KAAK,GAAG;IAChD,MAAM,CAAC,WAAW,eAAe,GAAG,KAAK,SAAS;IAClD,MAAM,iBAAiB,MAAM,UAAU,OACrC,OACAH,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,CAAC,UAAU,EAAE,IAAI,GAAG,CAAC,CACtD,EAAC,CACH;AACD,QAAI,gBAAgB;KAClB,SAAS,MAAM,eAAe,OAC5B,OACAA,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,CAAC,OAAO,EAAE,IAAI,GAAG,CAAC,CACnD,EAAC,CACH;AACD,gBAAW,MAAM,SAAS,QAAQ;MAChC,MAAM;AACN,UAAI,qBACF,KAAI,gBAAgB,QAClB,cAAc;UAEd,KAAI;OACF,cAAcI,4BAAO,aAAa,MAAM;MACzC,QAAO;OACN,cAAc;OACd,uBAAuB;MACxB;KAGN;AACD;IACD;GACF;AACD,OAAI,WAAW,QAAW;IACxB,SAAS,MAAM,KAAK,QAAQ,OAC1B,OACAJ,2BAAY,QAAQ,EAClB,WAAW,YAAY,SAAS,iBAAiB,CAClD,EAAC,CACH;AACD,eAAW,MAAM,SAAS,QAAQ;KAChC,MAAM;AACN,SAAI,qBACF,KAAI,gBAAgB,QAClB,cAAc;SAEd,KAAI;MACF,cAAcI,4BAAO,aAAa,MAAmB;KACtD,QAAO;MACN,cAAc;MACd,uBAAuB;KACxB;IAGN;GACF;EACF,SAAQ,GAAG;GACV,MAAM,YAAY,iBAAiB,EAAE;AACrC,SAAM;EACP;EACD,MAAM,YAAY,eAAe,eAAe,CAAE,EAAC;CACpD;AACF"}