RegexdrillThe i flag: any capitalization
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
A match anywhere counts. Match lines that contain the text error in any mix of upper and lower case, such as Error, ERROR or eRRor. Set the i flag.
What this exercise teaches
With the i flag, error matches every capitalization of those five letters. Listing the variants by hand, as in Error|ERROR|error, always misses some.
A hint if you get stuck
Flags change how the whole pattern behaves. The i flag makes letters match in both cases, so the pattern itself can stay in lowercase.
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