regex101: PCRE (Legacy) Match Workspace

Non-Capturing Group(?:(?<=\n)|(?<=\A))

1st Alternative(?<=\n)

Positive Lookbehind(?<=\n)

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

2nd Alternative(?<=\A)

Positive Lookbehind(?<=\A)

\Astart of string

Comment: Necessarily at the begining of a new line or start of string

Group code_all(?<code_all> (?<code_start> [ ]{0,3} # Possibly up to 3 leading spaces \`{3,} # 3 code marks (backticks) or more ) \n+ (?<code_content>.*?) # enclosed content \n+ (?<!`) \g{code_start} # balanced closing block marks (?!`) [ \t]* # possibly followed by some space \n )

Group code_start(?<code_start> [ ]{0,3} # Possibly up to 3 leading spaces \`{3,} # 3 code marks (backticks) or more )

Character Class[ ]{0,3}

{0,3}matches between 0 and 3 characters from the set below:

the literal (32₁₀ / 40₈ / 20₁₆)

Comment: Possibly up to 3 leading spaces

\`{3,}the literal ` (96₁₀ / 140₈ / 60₁₆) , repeated at least 3 times

Comment: 3 code marks (backticks) or more

\n+a line-feed (newline) character (ASCII 10), repeated at least once

Group code_content(?<code_content>.*?)

.*?any character, repeated any number of times

Comment: enclosed content

\n+a line-feed (newline) character (ASCII 10), repeated at least once

Negative Lookbehind(?<!`)

`the literal ` (96₁₀ / 140₈ / 60₁₆)

\g{code_start}the text saved by group code_start

Comment: balanced closing block marks

Negative Lookahead(?!`)

`the literal ` (96₁₀ / 140₈ / 60₁₆)

Character Class[ \t]*

*matches any number of characters from the set below:

the literal (32₁₀ / 40₈ / 20₁₆)

\ta tab character (ASCII 9)

Comment: possibly followed by some space

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

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

x modifier: extended. Ignores unescaped whitespace and comments outside character classes

s modifier: single line. Allows a dot to match line terminators

25 tokens

Regular Expression

(?:(?<=\n)|(?<=\A))                # Necessarily at the begining of a new line or start of string
(?<code_all>
    (?<code_start>
        [ ]{0,3}                    # Possibly up to 3 leading spaces
        \`{3,}                      # 3 code marks (backticks) or more
    )
    \n+
    (?<code_content>.*?)            # enclosed content
    \n+
    (?<!`)
    \g{code_start}                  # balanced closing block marks
    (?!`)
    [ \t]*                          # possibly followed by some space
    \n
)

New

Plop

```
<p>```
~~~
<p>```
```

Some *markdown*

```
<div>
    <html>
```

```
function test();
```

<div markdown="1">

```
<p>```
~~~
<p>```
```

```
<p>```
~~~
<p>```
```
~~~
<p>```
```
<p>```
~~~