What this snippet does
Without an access modifier keyword in the constructor, the parameter is treated as a normal function argument, not a class property.
Expected output
Compile Error: Property 'x' does not exist on type 'C'.
Why practise typing this
Typing classes 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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