What this snippet does
The logical OR (||) overrides all falsy values like 0 or '', while nullish coalescing (??) only overrides null/undefined.
Expected output
0 10
Why practise typing this
Typing advanced types 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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