Regular Expressions 101

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/
\n+^(I )?hope (it|this|that) helps?(\s|:-?\)|[!.])*$
/
gmi
\n
matches a line-feed (newline) character (ASCII 10)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
^ asserts position at start of a line
1st Capturing Group
(I )?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
I
matches the characters I literally (case insensitive)
hope
matches the characters hope literally (case insensitive)
2nd Capturing Group
(it|this|that)
1st Alternative
it
it
matches the characters it literally (case insensitive)
2nd Alternative
this
this
matches the characters this literally (case insensitive)
3rd Alternative
that
that
matches the characters that literally (case insensitive)
help
matches the characters help literally (case insensitive)
s
matches the character s with index 11510 (7316 or 1638) literally (case insensitive)
3rd Capturing Group
(\s|:-?\)|[!.])*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
1st Alternative
\s
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
2nd Alternative
:-?\)
: matches the character : with index 5810 (3A16 or 728) literally (case insensitive)
-
matches the character - with index 4510 (2D16 or 558) literally (case insensitive)
\) matches the character ) with index 4110 (2916 or 518) literally (case insensitive)
3rd Alternative
[!.]
Match a single character present in the list below
[!.]
!.
matches a single character in the list !. (case insensitive)
$ asserts position at the end of a line
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)
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gmi

Test String

Substitution

Processing...