Regular Expressions 101

1st Alternative\b(?<whole_word>[a-z])\k{whole_word}++\b(*SKIP)(*FAIL)

\ban ASCII word boundary

Group whole_word(?<whole_word>[a-z])

Character Class[a-z]

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

\k{whole_word}++the text saved by group whole_word, repeated at least once

\ban ASCII word boundary

(*SKIP)acts like (*PRUNE), but the next unanchored match attempt starts where (*SKIP) was reached instead of at the next subject character

(*FAIL)forces the current match attempt to fail at this position

2nd Alternative(?<not_whole_word>[a-z])\k{not_whole_word}++

Group not_whole_word(?<not_whole_word>[a-z])

Character Class[a-z]

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

\k{not_whole_word}++the text saved by group not_whole_word, repeated at least once

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

\b(?<whole_word>[a-z])\k{whole_word}++\b(*SKIP)(*FAIL)|(?<not_whole_word>[a-z])\k{not_whole_word}++

New

test ajjjo new
here bbb cca
here abbbbbc x
test jjka