Regular Expressions 101

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/
(?=[\s\S](MilesService OK))(?=[\s\S]+(PromotionsService OK))(?=[\s\S]+(ISearchPanelDao OK))
/
gm
Positive Lookahead
(?=[\s\S](MilesService OK))
Assert that the Regex below matches
Match a single character present in the list below
[\s\S]
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\S matches any non-whitespace character (equivalent to [^\r\n\t\f\v ])
1st Capturing Group
(MilesService OK)
MilesService OK
matches the characters MilesService OK literally (case sensitive)
Positive Lookahead
(?=[\s\S]+(PromotionsService OK))
Assert that the Regex below matches
Match a single character present in the list below
[\s\S]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\S matches any non-whitespace character (equivalent to [^\r\n\t\f\v ])
2nd Capturing Group
(PromotionsService OK)
PromotionsService OK
matches the characters PromotionsService OK literally (case sensitive)
Positive Lookahead
(?=[\s\S]+(ISearchPanelDao OK))
Assert that the Regex below matches
Match a single character present in the list below
[\s\S]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\S matches any non-whitespace character (equivalent to [^\r\n\t\f\v ])
3rd Capturing Group
(ISearchPanelDao OK)
ISearchPanelDao OK
matches the characters ISearchPanelDao OK 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