Regular Expressions 101

Explanation

Pro

Non-Capturing Group(?:\G(?!\A)|\h*(?=<\?))

1st Alternative\G(?!\A)

\Gstart of current search

Negative Lookahead(?!\A)

\Astart of string

2nd Alternative\h*(?=<\?)

\h*any horizontal whitespace character, repeated any number of times

Positive Lookahead(?=<\?)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

Group 1(.*(?=(?:(?!<\?)[\s\S])*?(?<=\?>)))

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

Positive Lookahead(?=(?:(?!<\?)[\s\S])*?(?<=\?>))

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

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

Negative Lookahead(?!<\?)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

Character Class[\s\S]

\sany whitespace character

\Sany non-whitespace character

Positive Lookbehind(?<=\?>)

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

>the literal > (62₁₀ / 76₈ / 3E₁₆)

Global pattern flags

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

Detailed match information will be displayed here automatically.

25 tokens

(?:\G(?!\A)|\h*(?=<\?))(.*(?=(?:(?!<\?)[\s\S])*?(?<=\?>)))

New

<html><?php test(); ?>
  <head>
    <?php test();

    ?>
  </head>
  <body>
  </body>
<html>

<html><?php test(); ?>
  <head>
    <?php test();

    ?>
  </head>
  <body>
  </body>
<html>