What this snippet does
Properly implementing the done state ensures loops and spread operators terminate correctly without infinite loops.
Expected output
[ 1, 2 ]
Why practise typing this
Typing symbols & iterators 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.
More TypeScript practice
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- Implementing a basic iterator interfaceSymbols & Iterators · advanced
- Forgetting to return done: trueSymbols & Iterators · advanced
- Creating a basic generator functionSymbols & Iterators · advanced