/
re
\.
n
/
Privacy
POSIX Regex Tester
Language
JavaScript
Python
Python (regex)
Java
.NET (C#)
PCRE1 (C)
PHP (PCRE2)
Go
RE2 (C++)
Rust
Rust (fancy-regex)
Ruby
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GNU grep -E (C)
ICU (Swift, Android)
Vim
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Pattern
Code
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Pattern
/
/
Flags
g
, Global, every match
i
, Ignore case
m
, Newline-sensitive: ^ $ at lines, . and [^…] skip newlines
s
, Dot matches newline
x
, Verbose
U
, Ungreedy
u
, Unicode
y
, Sticky
a
, ASCII only
n
, Explicit capture
v
, Version 1 behaviour
b
, Basic syntax (BRE), with back-references
w
, Unicode word boundaries
Test text 1
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ReDoS
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