Regular Expressions 101

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/
([\wá-ú])\s(?=(¿|¡)[A--Ú])
/
gm
1st Capturing Group
([\wá-ú])
Match a single character present in the list below
[\wá-ú]
\w matches any word character (equivalent to [a-zA-Z0-9_])
à matches the character à with index 19510 (C316 or 3038) literally (case sensitive)
¡-à matches a single character in the range between ¡ (index 161) and à (index 195) (case sensitive)
º matches the character º with index 18610 (BA16 or 2728) literally (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
Positive Lookahead
(?=(¿|¡)[A--Ú])
Assert that the Regex below matches
2nd Capturing Group
(¿|¡)
1st Alternative
¿
¿
matches the characters ¿ literally (case sensitive)
2nd Alternative
¡
¡
matches the characters ¡ literally (case sensitive)
Match a single character present in the list below
[A--Ú]
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
à matches the character à with index 19510 (C316 or 3038) literally (case sensitive)
 matches a single character in the range between  (index 129) and à (index 195) (case sensitive)
š matches the character š with index 35310 (16116 or 5418) 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.

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...