Regular Expressions 101

Pro

^start of line

Negative Lookahead(?![a-z\d]*(?: *\[[^[\]\r\n]*\])+\r?\n)

Character Class[a-z\d]*

*matches any number of characters from the set below:

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

\da digit

Non-Capturing Group(?: *\[[^[\]\r\n]*\])+

+repeats the group contents below at least once:

*the literal (32₁₀ / 40₈ / 20₁₆) , repeated any number of times

\[the literal [ (91₁₀ / 133₈ / 5B₁₆)

Negated Character Class[^[\]\r\n]*

*matches any number of characters outside the set below:

[the literal [ (91₁₀ / 133₈ / 5B₁₆)

\]the literal ] (93₁₀ / 135₈ / 5D₁₆)

\ra carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

\]the literal ] (93₁₀ / 135₈ / 5D₁₆)

\r?optionally matches a carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

.*any character (except for line terminators), repeated any number of times

Global pattern flags

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

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

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.

25 tokens

Regular Expression

^(?![a-z\d]*(?: *\[[^[\]\r\n]*\])+\r?\n).*

green          [foo] [foo1]
red             [foo]
blue                  [foo] [foo1] [foo2]
yellow             [foo2]
green      cat [foo]
green          [foo]    foo1]
red             [goo]
red             [foo][who
pink                  [foo3]
reddish       [foo]

Substitution

green          [foo] [foo1]
red             [foo]
blue                  [foo] [foo1] [foo2]
yellow             [foo2]
green      cat [foo]
green          [foo]    foo1]
red             [goo]
red             [foo][who
pink                  [foo3]
reddish       [foo]