Regular Expressions 101

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/
([а-яё])"(?=[а-яё])
/
gi
1st Capturing Group
([а-яё])
Match a single character present in the list below
[а-яё]
а-я matches a single character in the range between а (index 1072) and я (index 1103) (case insensitive)
ё matches the character ё with index 110510 (45116 or 21218) literally (case insensitive)
" matches the character " with index 3410 (2216 or 428) literally (case insensitive)
Positive Lookahead
(?=[а-яё])
Assert that the Regex below matches
Match a single character present in the list below
[а-яё]
а-я matches a single character in the range between а (index 1072) and я (index 1103) (case insensitive)
ё matches the character ё with index 110510 (45116 or 21218) literally (case insensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
gi

Test String

Substitution

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Code Generator

Generated Code

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions