Regular Expressions 101

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/
customers(?=(?:[^><]*<[^<>]*>)*[^><]*$)
/
gm
customers
matches the characters customers literally (case sensitive)
Positive Lookahead
(?=(?:[^><]*<[^<>]*>)*[^><]*$)
Assert that the Regex below matches
Non-capturing group
(?:[^><]*<[^<>]*>)*
* matches the previous token between zero 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 a single character in the list >< (case sensitive)
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
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 a single character in the list <> (case sensitive)
> matches the character > with index 6210 (3E16 or 768) literally (case sensitive)
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 a single character in the list >< (case sensitive)
$ 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

Substitution

Processing...