Regular Expressions 101

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/
[ |\t]+\*\s+@access\s+(?:private|protected|public)\n
/
gm
Match a single character present in the list below
[ |\t]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
|
matches a single character in the list | (case sensitive)
\t matches a tab character (ASCII 9)
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
@access
matches the characters @access literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Non-capturing group
(?:private|protected|public)
1st Alternative
private
private
matches the characters private literally (case sensitive)
2nd Alternative
protected
protected
matches the characters protected literally (case sensitive)
3rd Alternative
public
public
matches the characters public literally (case sensitive)
\n matches a line-feed (newline) character (ASCII 10)
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