Regular Expressions 101

Negative Lookbehind(?<![^\n])

Negated Character Class[^\n]

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

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

*?repeats the group contents below any number of times:

Negative Lookahead(?!\/\/)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Negated Character Class[^\r\n]

\ra carriage return (ASCII 13)

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

whilethe literal text while (case sensitive)

Negated Character Class[^\r\n]+

+matches at least one character outside the set below:

\ra carriage return (ASCII 13)

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

Character Class[\s=(]

\sany whitespace character

=the literal = (61₁₀ / 75₈ / 3D₁₆)

(the literal ( (40₁₀ / 50₈ / 28₁₆)

eachthe literal text each (case sensitive)

Character Class[\s(]

\sany whitespace character

(the literal ( (40₁₀ / 50₈ / 28₁₆)

Negative Lookahead(?!(?:(?!\/\*)[\S\s])*?\*\/)

Non-Capturing Group(?:(?!\/\*)[\S\s])*?

*?repeats the group contents below any number of times:

Negative Lookahead(?!\/\*)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

\*the literal * (42₁₀ / 52₈ / 2A₁₆)

Character Class[\S\s]

\Sany non-whitespace character

\sany whitespace character

\*the literal * (42₁₀ / 52₈ / 2A₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Global pattern flags

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?<![^\n])(?:(?!\/\/)[^\r\n])*?while[^\r\n]+[\s=(]each[\s(](?!(?:(?!\/\*)[\S\s])*?\*\/)

Test String
New

// bar bar

while (list($key, $value) = each($_GET))

/* some code
  while (list($key, $value) = each($_GET))
  some code
*/

while (list($key, $value) = each($_GET))

Regular Expression

Test StringNew

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Test String
New

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