Regular Expressions 101

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/
\bpayments\W+(?:\w+\W+){1,9}?(?<highlight>\d{1,3})\s+?days\b
/
gm
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
payments
matches the characters payments literally (case sensitive)
\W
matches any non-word character (equivalent to [^a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Non-capturing group
(?:\w+\W+){1,9}?
{1,9}? matches the previous token between 1 and 9 times, as few times as possible, expanding as needed (lazy)
\w
matches any word character (equivalent to [a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\W
matches any non-word character (equivalent to [^a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Named Capture Group highlight
(?<highlight>\d{1,3})
\d
matches a digit (equivalent to [0-9])
{1,3} matches the previous token between 1 and 3 times, as many times as possible, giving back as needed (greedy)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
+? matches the previous token between one and unlimited times, as few times as possible, expanding as needed (lazy)
days
matches the characters days literally (case sensitive)
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
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

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