What this snippet does
The 'as const' assertion tells TypeScript to infer the most specific literal type possible, preventing widening to the base type.
Expected output
hello
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