Regular Expressions 101

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/
\b[A-Z]+(?:[-'][A-Z]+)*(?:\/|(?!\S))
/
gm
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
Match a single character present in the list below
[A-Z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
Non-capturing group
(?:[-'][A-Z]+)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[-']
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
This hyphen is treated literally, which might be confusing for others. Consider escaping it or placing at the start or end of the class!
' matches the character ' with index 3910 (2716 or 478) literally (case sensitive)
Match a single character present in the list below
[A-Z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
Non-capturing group
(?:\/|(?!\S))
1st Alternative
\/
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
2nd Alternative
(?!\S)
Negative Lookahead
(?!\S)
Assert that the Regex below does not match
\S matches any non-whitespace character (equivalent to [^\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Generated Code

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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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions