Builder pattern using polymorphic this in TypeScript

What this snippet does

Using 'this' in inherited methods ensures that chaining returns the subclass instance, preserving access to subclass methods.

Expected output

UserQuery { limit: 10, active: true }

Why practise typing this

Typing advanced classes & oop 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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