RegexdrillBackreference: matching HTML tags
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
The whole line must match. Match an opening tag, any text and a closing tag with the same name, like <b>bold</b>. Tag names are word characters with no attributes, and the text can be empty.
What this exercise teaches
<(\w+)>.*</\1> captures the name of the opening tag and \1 repeats exactly that text in the closing tag. Writing \w+ twice would accept <b>bold</i>, because each \w+ matches on its own.
A hint if you get stuck
Capture the tag name in a group, then use \1 in the closing tag to demand the same name again.
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