What this snippet does
Arrow functions capture 'this' from their surrounding scope, which is undefined in class/global strict mode.
Expected output
TypeError: Cannot read properties of undefined (reading 'val')
Why practise typing this
Typing functions 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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