javascript / intermediate
Snippet
Object Destructuring with Aliasing and Defaults
Destructuring can extract nested properties and assign them to new variable names (aliasing) in a single step. You can also provide default values that are used if a property is missing or undefined.
snippet.js
javascript
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const userResponse = { id: 42, meta: { lastLogin: '2023-01-01' } };const {id: userId,meta: { lastLogin: loginDate },role = 'guest'} = userResponse;console.log(userId, loginDate, role);
Breakdown
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id: userId
Extracts the 'id' property but assigns its value to a new constant named 'userId'.
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role = 'guest'
Declares a 'role' variable with a fallback value of 'guest' if the property doesn't exist in userResponse.