Regular Expressions 101

\<the literal < (60₁₀ / 74₈ / 3C₁₆)

Group 1(\w+)

\w+any word character, repeated at least once

Non-Capturing Group(?:\s[^<>]+)?

?repeats the group contents below at most once:

\sany whitespace character

Negated Character Class[^<>]+

+matches at least one character outside the set below:

<the literal < (60₁₀ / 74₈ / 3C₁₆)

>the literal > (62₁₀ / 76₈ / 3E₁₆)

\>the literal > (62₁₀ / 76₈ / 3E₁₆)

Negative Lookahead(?!(?:.|\n)*\<\/\1\>)

Non-Capturing Group(?:.|\n)*

*repeats the group contents below any number of times:

1st Alternative.

.any character (except for line terminators)

2nd Alternative\n

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

\<the literal < (60₁₀ / 74₈ / 3C₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

\1the text saved by group 1

\>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.

Search reference

Regular Expression

\<(\w+)(?:\s[^<>]+)?\>(?!(?:.|\n)*\<\/\1\>)

New

<a href="a_url" class="url" target="_blank">
   <img ng-src=" {{getImageUrl('homeHelp64.jpg')}}" alt="?" width="16" height="16">
      <alt>
	  </aldt> // invalid
   </imgv> // invalid
</a>