regex101: PCRE (Legacy) Substitution Workspace

<athe literal text <a (case insensitive)

Non-Capturing Group(?:(?!</?a>).)+?

+?repeats the group contents below at least once:

Negative Lookahead(?!</?a>)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

/?optionally matches the literal / (47₁₀ / 57₈ / 2F₁₆)

a>the literal text a> (case insensitive)

.any Unicode character

/moscow/the literal text /moscow/ (case insensitive)

.+?any Unicode character, repeated at least once

</a>the literal text </a> (case insensitive)

Global pattern flags

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

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

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

u modifier: unicode. Treats the pattern and subject as UTF-16

Search reference

Regular Expression

<a(?:(?!</?a>).)+?/moscow/.+?</a>

Test String
New

<a href="/moscow/">ссылка</a>
<a href="/lalala/moscow/">ссылка</a>
<a href="/moscow/lalala">ссылка</a>
<a href="/lalala">ссылка</a>
<a href="/">ссылка</a>
<a style="color: red">ссылка</a>
<a style="color: red" href="/moscow/">ссылка</a>
<a href="/moscow/" style="color: red">ссылка</a>

<a href="/lalala/moscow/">/moscow/</a>
<a href="/lalala/">/moscow/</a>

Regular Expressions 101

Regular Expression

Test String
New

Substitution
Processing...

Regular Expression

Test StringNew

SubstitutionProcessing...

Test String
New

Substitution
Processing...