javascript / intermediate
Snippet
Meta-Programming with Reflect
The Reflect API provides methods for interceptable JavaScript operations. Unlike the Object class, Reflect methods return a boolean to indicate success and offer a more consistent way to handle property definition and inspection.
snippet.js
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const user = { id: 42 };Reflect.defineProperty(user, 'hidden', {value: 'secret',enumerable: false});console.log(Reflect.has(user, 'id'));console.log(Reflect.ownKeys(user));
Breakdown
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Reflect.defineProperty(user, 'hidden', { ... });
Defines a new property on the object, returning true if successful.
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enumerable: false
Makes the property invisible during standard loops like for...in.
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Reflect.has(user, 'id');
Checks if the property exists on the object or its prototype chain.
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Reflect.ownKeys(user);
Returns an array of all own property keys, including non-enumerable ones.