What this snippet does
Const enums are inlined by the compiler, which breaks single-file transpilation; isolatedModules flags them as errors.
Expected output
Compile Error: Const enums are not allowed when 'isolatedModules' is enabled.
Why practise typing this
Typing tsconfig & compiler 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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- Preventing null assignment to stringstsconfig & Compiler · intermediate
- Checking for null before accessing propertiestsconfig & Compiler · intermediate
- Array index access returns T instead of T | undefinedtsconfig & Compiler · intermediate