RegexdrillWord boundaries: replace a whole word
A regex exercise from Regexdrill. Solve it with a pattern box with live highlighting in your browser, checked against hidden test strings, and it is checked the moment you submit.
The task
Replace every whole word cat with dog. Words that only contain cat, like catalog or bobcat, stay unchanged.
What this exercise teaches
\bcat\b with the g flag replaces cat only where it stands as its own word.
A hint if you get stuck
\b on both sides of the word keeps it from matching inside longer words.
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