Dart cache function implementation in several ways

Single variable cache

Advantages: convenient and easy to understand

Disadvantages: Each Cache function requires an additional *Cache variable to be maintained

String _getNativeVersionCache;
StringgetNativeVersion() { _getNativeVersionCache ?? = Native.getVersion();return _getNativeVersionCache;
}
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Cache helper function

Advantages: Frequently used, only one memorize function is exposed

Disadvantages: Memorize often requires multiple overloading (functions that process different parameters)

T Function() memorize<T>(T Function() fun) {
	T cache;
	return() { cache ?? = fun();return cache;
	};
}

String _getNativeVersion() {
	return Native.getVersion();
}

String getNativeVersion = memorize(_getNativeVersion);
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Caching auxiliary objects

Advantages: convenient, easy to understand, only need to disclose one person

Disadvantages: Not often used

Map<String.dynamic> memorize = {};
String getNativeVersion() {
	memorize['getNativeVersion']???? = Native.getVersion();return memorize['getNativeVersion'];
}
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conclusion