Regular Expressions 101

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/
(?i)(\b|[¡¿])(?<uno>[^\s]+\s[^,]+),\s(\k<uno>)([?!]|\b)
/
gm
(?i)
match the remainder of the pattern with the following effective flags: gmi
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
1st Capturing Group
(\b|[¡¿])
1st Alternative
\b
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
2nd Alternative
[¡¿]
Match a single character present in the list below
[¡¿]
¡¿
matches a single character in the list ¡¿ (case insensitive)
Named Capture Group uno
(?<uno>[^\s]+\s[^,]+)
Match a single character not present in the list below
[^\s]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
Match a single character not present in the list below
[^,]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
, matches the character , with index 4410 (2C16 or 548) literally (case insensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case insensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
3rd Capturing Group
(\k<uno>)
\k<uno> matches the same text as most recently matched by the capturing group named uno
4th Capturing Group
([?!]|\b)
1st Alternative
[?!]
Match a single character present in the list below
[?!]
?!
matches a single character in the list ?! (case insensitive)
2nd Alternative
\b
\b assert position at a word boundary: (^\w|\w$|\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

Substitution

Processing...