stateful regex in JavaScript

What this snippet does

A regex with /g is stateful — it remembers lastIndex between calls. Create a new instance each time or reset lastIndex = 0.

Expected output

true
7
true
15
false
0

Why practise typing this

Typing regex 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.

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