TypeScript

Declaring an unused variable in TypeScript

TypeScriptStrict Compiler FlagsnoUnusedLocals & noUnusedParametersintermediate

What this snippet does

noUnusedLocals throws an error if a variable is declared but never read, keeping the codebase clean.

Expected output

Compile Error: 'x' is declared but its value is never read.

Why practise typing this

Typing strict compiler flags 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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