重构 if-else 或 switch 成 table

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if (season === "summer") {
  return "It's 30, hot!";
} else if (season === "winter") {
  return "It's 2, cold!";
} else {
  return "It's 20, good!";
}

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switch (season) {
	case "summer": return "It's 30, hot!";
	case "winter": return "It's 2, cold!";
	default: return "It's 20, good!";
}

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const seasonConfig = {
	summer: { text: "hot!", temperature: 30 },
	winter: { text: "cold!", temperature: 2 },
	defaultKey: { text: "good!", temperature: 20 }
};
function getValueFromTable(table, key, defaultKey) {
	return table[key] || table[defaultKey];
}
const summer = getValueFromTable(seasonConfig, "summer", "defaultKey");
summerDOM.innerHTML = `It's ${summer.temperature}, ${summer.text}`;

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const table = {
	summer: { text: "hot!", temperature: 30 },
	winter: { text: "cold!", temperature: 2 },
	defaultKey: { text: "good!", temperature: 20 }
};