What this snippet does
Arrays declared with 'as const' become readonly tuples, preventing mutation methods like push at compile time.
Expected output
Compile Error: Property 'push' does not exist on type 'readonly [1, 2]'.
Why practise typing this
Typing inference deep dive code builds muscle memory for the symbols and indentation TypeScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.
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- Const type parameters forcing immutabilityInference Deep Dive · advanced
- Declaring variables with primitive typesBasic Types · beginner