Regular Expressions 101

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/
(\/{3})\n( ){8}\/{3} (.+) \n( ){8}(\/){3}
/
gm
1st Capturing Group
(\/{3})
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{3} matches the previous token exactly 3 times
\n matches a line-feed (newline) character (ASCII 10)
2nd Capturing Group
( ){8}
{8} matches the previous token exactly 8 times
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
matches the character with index 3210 (2016 or 408) literally (case sensitive)
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{3} matches the previous token exactly 3 times
matches the character with index 3210 (2016 or 408) literally (case sensitive)
3rd Capturing Group
(.+)
.
matches any character (except for line terminators)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
matches the character with index 3210 (2016 or 408) literally (case sensitive)
\n matches a line-feed (newline) character (ASCII 10)
4th Capturing Group
( ){8}
{8} matches the previous token exactly 8 times
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
matches the character with index 3210 (2016 or 408) literally (case sensitive)
5th Capturing Group
(\/){3}
{3} matches the previous token exactly 3 times
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
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.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...