Regular Expressions 101

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/
(?<year>\d{4})-(?<month>[01][0-9])-(?<day>[0123][0-9])
/
gm
All the errors detected are listed below, from left to right, as they appear in the pattern.
? The preceding token is not quantifiable
? The preceding token is not quantifiable
? The preceding token is not quantifiable
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
gm

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/

Regular Expressions 101

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