3. Interpreter Pattern:

The Interpreter pattern is used for parsing expressions and executing them based on a defined grammar.

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Example in React:

Suppose you want to create a simple calculator in React that can evaluate mathematical expressions.

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import React, { useState } from 'react';

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const InterpreterPatternExample = () => {

  const [expression, setExpression] = useState('');

  const [result, setResult] = useState('');

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  const evaluateExpression = () => {

    try {

      const evalResult = eval(expression);

      setResult(evalResult);

    } catch (error) {

      setResult('Error');

    }

  };

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  return (

    <div>

      <input

        type="text"

        value={expression}

        onChange={(e) => setExpression(e.target.value)}

      />

      <button onClick={evaluateExpression}>Evaluate</button>

      <p>Result: {result}</p>

    </div>

  );

};

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export default InterpreterPatternExample;

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