initial commit

.eslintrc.js

@@ -0,0 +1,38 @@
+module.exports = {
+  extends: [
+    "airbnb-base",
+    "eslint:recommended",
+    "prettier",
+    "plugin:@typescript-eslint/recommended",
+  ],
+  parserOptions: {
+    ecmaVersion: 12,
+    parser: "@typescript-eslint/parser",
+    sourceType: "module",
+  },
+  plugins: ["@typescript-eslint"],
+  rules: {
+    "@typescript-eslint/explicit-module-boundary-types": 0,
+    "@typescript-eslint/no-empty-function": 0,
+    "@typescript-eslint/no-shadow": ["error"],
+    "@typescript-eslint/no-use-before-define": ["error", "nofunc"],
+    "@typescript-eslint/no-unused-vars": ["warn", { args: "none" }],
+    "comma-dangle": ["error", "never"],
+    "camelcase": 0,
+    "class-methods-use-this": 0,
+    "import/extensions": 0,
+    "import/no-extraneous-dependencies": ["error", {"devDependencies": ["**/*.test.ts"]}],
+    "import/no-unresolved": 0,
+    "import/prefer-default-export": 0,
+    "keyword-spacing": "error",
+    "max-classes-per-file": 0,
+    "max-len": ["error", { code: 100, tabWidth: 2, ignoreComments: true }],
+    "no-bitwise": "off",
+    "no-console": 0,
+    "no-restricted-syntax": 0,
+    "no-shadow": 0,
+    "no-underscore-dangle": 0,
+    "no-use-before-define": 0,
+    "semi": ["error", "always"],
+  },
+};

.gitignore

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+node_modules/
+dist/
+lib/
+.turbo
+.eslintcache

.husky/pre-commit

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+#!/usr/bin/env sh
+. "$(dirname -- "$0")/_/husky.sh"
+
+yarn precommit

.prettierignore

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+babel.config.js
+jest.config.js
+.eslintrc.js

README.md

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+# langchainjs

babel.config.js

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+//babel.config.js
+module.exports = {presets: ['@babel/preset-env']}

jest.config.js

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+/** @type {import('ts-jest').JestConfigWithTsJest} */
+module.exports = {
+  preset: 'ts-jest/presets/js-with-ts',
+  testEnvironment: 'node',
+  transform: {
+    "^.+\\.(ts|tsx)$": "ts-jest",
+    "^.+\\.(js)$": "babel-jest",
+  },
+  transformIgnorePatterns: [
+  ],
+};

package.json

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+{
+  "name": "langchain",
+  "version": "0.0.1",
+  "description": "Typescript bindings for langchain",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "files": [
+    "dist/"
+  ],
+  "scripts": {
+    "build": "tsc --declaration --outDir dist/",
+    "lint": "eslint src",
+    "lint:fix": "yarn lint --fix",
+    "precommit": "tsc --noEmit && lint-staged",
+    "clean": "rm -rf dist/",
+    "prepack": "yarn build",
+    "test": "jest",
+    "prepare": "husky install"
+  },
+  "author": "Langchain",
+  "license": "MIT",
+  "devDependencies": {
+    "@babel/preset-env": "^7.20.2",
+    "@jest/globals": "^29.4.2",
+    "@tsconfig/recommended": "^1.0.2",
+    "@typescript-eslint/eslint-plugin": "^5.51.0",
+    "@typescript-eslint/parser": "^5.51.0",
+    "babel-jest": "^29.4.2",
+    "eslint": "^8.33.0",
+    "eslint-config-airbnb-base": "^15.0.0",
+    "eslint-config-prettier": "^8.6.0",
+    "eslint-plugin-import": "^2.27.5",
+    "eslint-plugin-prettier": "^4.2.1",
+    "husky": "^8.0.3",
+    "jest": "^29.4.2",
+    "lint-staged": "^13.1.1",
+    "prettier": "^2.8.3",
+    "ts-jest": "^29.0.5",
+    "typescript": "^4.9.5"
+  },
+  "dependencies": {
+    "node-fetch": "^3.3.0",
+    "yaml": "^2.2.1"
+  },
+  "lint-staged": {
+    "src/**/*.{ts,tsx}": [
+      "prettier --write --ignore-unknown",
+      "eslint --cache --fix"
+    ]
+  }
+}

src/index.ts

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+export {
+  PromptTemplate,
+  BasePromptTemplate,
+  FewShotPromptTemplate,
+} from "./prompt";

src/prompt/base.ts

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+import { BaseOutputParser } from "./parser";
+import {
+  PromptTemplateInput,
+  SerializedPromptTemplate,
+  PromptTemplate,
+  FewShotPromptTemplateInput,
+  SerializedFewShotTemplate,
+  FewShotPromptTemplate,
+} from "./index";
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export type InputValues = Record<string, any>;
+
+type SerializedBasePromptTemplate =
+  | SerializedPromptTemplate
+  | SerializedFewShotTemplate
+  | (Omit<SerializedPromptTemplate, "_type"> & { _type: undefined });
+
+export interface BasePromptTemplateInput {
+  inputVariables: string[];
+  outputParser?: BaseOutputParser;
+}
+
+type ConstructorInput = FewShotPromptTemplateInput | PromptTemplateInput;
+
+export abstract class BasePromptTemplate implements BasePromptTemplateInput {
+  inputVariables: string[];
+
+  outputParser?: BaseOutputParser;
+
+  constructor(input: ConstructorInput) {
+    const { inputVariables } = input;
+    if (inputVariables.includes("stop")) {
+      throw new Error(
+        "Cannot have an input variable named 'stop', as it is used internally, please rename."
+      );
+    }
+    Object.assign(this, input);
+  }
+
+  abstract format(values: InputValues): string;
+
+  abstract _getPromptType(): string;
+
+  abstract serialize(): SerializedBasePromptTemplate;
+
+  // Deserializing needs to be async because templates (e.g. few_shot) can
+  // reference remote resources that we read asynchronously with a web
+  // request.
+  static async deserialize(
+    data: SerializedBasePromptTemplate
+  ): Promise<BasePromptTemplate> {
+    switch (data._type) {
+      case "prompt":
+        return PromptTemplate.deserialize(data);
+      case undefined:
+        return PromptTemplate.deserialize({ ...data, _type: "prompt" });
+      case "few_shot":
+        return FewShotPromptTemplate.deserialize(data);
+      default:
+        throw new Error(
+          `Invalid prompt type in config: ${
+            (data as SerializedBasePromptTemplate)._type
+          }`
+        );
+    }
+  }
+}