typescript / beginner
Snippet
Readonly Properties in Interfaces
The 'readonly' modifier ensures that a property can only be assigned a value when the object is first created, preventing later modifications.
snippet.ts
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interface UserProfile {readonly id: number;username: string;}const user: UserProfile = { id: 99, username: "coder123" };// user.id = 100; // This would cause a compile error
Breakdown
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readonly id: number;
Marks the 'id' property as read-only, preventing reassignment after initialization.
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user.id = 100;
Demonstrates that trying to change a readonly property results in a TypeScript error.