RegexdrillNamed groups in a replacement
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
Rewrite every date written YYYY-MM-DD as DD.MM.YYYY. Capture the parts in named groups and refer to them by name in the replacement. Leave everything else unchanged.
What this exercise teaches
(?<y>\d{4})-(?<m>\d{2})-(?<d>\d{2}) with the replacement $<d>.$<m>.$<y> and the g flag reorders every date. Named references still read correctly when groups are moved or added, which $1 and $2 do not. Without named groups in the pattern, $<d> is inserted as literal text.
A hint if you get stuck
In a JavaScript replacement string, $<name> inserts the group called name.
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