Regular Expressions 101

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/
(^| )text($| )
/
gm
1st Capturing Group
(^| )
1st Alternative
^
^ asserts position at start of a line
2nd Alternative
matches the character with index 3210 (2016 or 408) literally (case sensitive)
text
matches the characters text literally (case sensitive)
2nd Capturing Group
($| )
1st Alternative
$
$ asserts position at the end of a line
2nd Alternative
matches the character with index 3210 (2016 or 408) 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