Regular Expressions 101

^start of line

Non-Capturing Group(?:[^{\n]|{(?!{)|{{2}(?:dog|cat)}{2})+

+repeats the group contents below at least once:

1st Alternative[^{\n]

Negated Character Class[^{\n]

{the literal { (123₁₀ / 173₈ / 7B₁₆)

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

2nd Alternative{(?!{)

{the literal { (123₁₀ / 173₈ / 7B₁₆)

Negative Lookahead(?!{)

{the literal { (123₁₀ / 173₈ / 7B₁₆)

3rd Alternative{{2}(?:dog|cat)}{2}

{{2}the literal { (123₁₀ / 173₈ / 7B₁₆) , repeated exactly 2 times

Non-Capturing Group(?:dog|cat)

1st Alternativedog

dogthe literal text dog (case sensitive)

2nd Alternativecat

catthe literal text cat (case sensitive)

}{2}the literal } (125₁₀ / 175₈ / 7D₁₆) , repeated exactly 2 times

$end of line

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

^(?:[^{\n]|{(?!{)|{{2}(?:dog|cat)}{2})+$

New

I own a {{dog}} and {{cat}} but not fish
I own a fish
I own a {{cow}}
I own a {{dog}} and a {{cow}}
I own a {{cat}} hah
I {own} a {{dog}}
I {own} a {{cat}} and {cow}
I own a {cow}

Regular Expression

Extraction