What this snippet does
Returning this from every mutating method enables fluent chaining — makes the API read like a sentence.
Expected output
SELECT * FROM users WHERE age > 18 AND active = true LIMIT 10
Why practise typing this
Typing classes code builds muscle memory for the symbols and indentation JavaScript 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 JavaScript practice
- class syntaxClasses · beginner
- class extendsClasses · intermediate
- static membersClasses · intermediate
- private fieldsClasses · intermediate
- abstract methodsClasses · advanced
- mixinsClasses · advanced