Regular Expressions 101

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/
\/[^/]+[._-]v?\d+(\.\d+(\.\d+)?)?[^/]*\.\w+$ |\/v?\d+\.\d+\.\d+.*?\/.*$ |\/v\d.*?\/.*$ |\/([^/]+[._-])?([0-9a-f]{5,})([._-].*?)?\.\w+$
/
gm
1st Alternative
\/[^/]+[._-]v?\d+(\.\d+(\.\d+)?)?[^/]*\.\w+$
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Match a single character not present in the list below
[^/]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Match a single character present in the list below
[._-]
._
matches a single character in the list ._ (case sensitive)
- 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!
v
matches the character v with index 11810 (7616 or 1668) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
1st Capturing Group
(\.\d+(\.\d+)?)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
(\.\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character not present in the list below
[^/]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\w
matches any word character (equivalent to [a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
matches the character with index 1010 (A16 or 128) literally (case sensitive)
2nd Alternative
\/v?\d+\.\d+\.\d+.*?\/.*$
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
v
matches the character v with index 11810 (7616 or 1668) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
matches the character with index 1010 (A16 or 128) literally (case sensitive)
3rd Alternative
\/v\d.*?\/.*$
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
v matches the character v with index 11810 (7616 or 1668) literally (case sensitive)
\d matches a digit (equivalent to [0-9])
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
matches the character with index 1010 (A16 or 128) literally (case sensitive)
4th Alternative
\/([^/]+[._-])?([0-9a-f]{5,})([._-].*?)?\.\w+$
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
3rd Capturing Group
([^/]+[._-])?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character not present in the list below
[^/]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Match a single character present in the list below
[._-]
._
matches a single character in the list ._ (case sensitive)
- 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!
4th Capturing Group
([0-9a-f]{5,})
Match a single character present in the list below
[0-9a-f]
{5,} matches the previous token between 5 and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
a-f matches a single character in the range between a (index 97) and f (index 102) (case sensitive)
5th Capturing Group
([._-].*?)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[._-]
._
matches a single character in the list ._ (case sensitive)
- 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 any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\w
matches any word character (equivalent to [a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
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