What this snippet does
Numeric enums generate a reverse mapping object at runtime, allowing value-to-key lookups which can be unexpected.
Expected output
Up
Why practise typing this
Typing basic 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.
More TypeScript practice
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