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Community Patterns
Search among 6,000 community submitted regex patterns...
0
text has numbers
ECMAScript (JavaScript)
text has numbers
Submitted by
vijay
-
10 months ago
1
...
298
299
300
Add a string to a comma-separated list if not already in list
1
Regular Expression
PCRE (PHP <7.3)
/
^
(
text
[
]
*
=
[
]
*
)
'
(
(?
(?!
item_1
[
,
]
?
)
.
)*
)
'
/
gm
Open regex in editor
Description
matches only lines that do not contain the string
uses negative look arounds
appends the new item always to the back
suffers from a leading comma in case the list was empty
Submitted by
@ubunatic
-
8 years ago