48 lines
1.4 KiB
JavaScript
48 lines
1.4 KiB
JavaScript
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import { Parser } from "expr-eval";
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import { Tool } from "@langchain/core/tools";
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/**
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* The Calculator class is a tool used to evaluate mathematical
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* expressions. It extends the base Tool class.
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* @example
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* ```typescript
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* import { Calculator } from "@langchain/community/tools/calculator";
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*
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* const calculator = new Calculator();
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* const sum = await calculator.invoke("99 + 99");
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* console.log("The sum of 99 and 99 is:", sum);
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* // The sum of 99 and 99 is: 198
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* ```
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*/
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export class Calculator extends Tool {
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constructor() {
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super(...arguments);
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Object.defineProperty(this, "name", {
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enumerable: true,
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configurable: true,
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writable: true,
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value: "calculator"
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});
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Object.defineProperty(this, "description", {
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enumerable: true,
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configurable: true,
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writable: true,
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value: `Useful for getting the result of a math expression. The input to this tool should be a valid mathematical expression that could be executed by a simple calculator.`
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});
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}
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static lc_name() {
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return "Calculator";
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}
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get lc_namespace() {
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return [...super.lc_namespace, "calculator"];
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}
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/** @ignore */
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async _call(input) {
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try {
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return Parser.evaluate(input).toString();
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}
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catch (error) {
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return "I don't know how to do that.";
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}
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}
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}
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