What this snippet does
TypeScript infers the parameter types of arrow functions based on the type of the variable they are assigned to.
Expected output
1.00
Why practise typing this
Typing contextual typing 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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