Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gmi

Test String

Code Generator

Language

Generated Code

$re = '/{#include\s*([\w.]+)\s*}/mi'; $str = '{#include header.html} <header class="bg-gradient-to-r from-purple-700 to-indigo-800 shadow-lg w-full"> <div class="max-w mx-auto px-4 sm:px-6 lg:px-8 py-6"> <div class="flex flex-col items-center justify-between md:flex-row"> <a href="/"> <h1 class="mb-4 text-2xl font-bold text-white md:mb-0 md:text-3xl">Header</h1> </a> <nav class="flex space-x-4"> <a href="/"> <a href="#" class="text-white transition duration-150 ease-in-out hover:text-purple-200">Home</a> </a> <a href="#" class="text-white transition duration-150 ease-in-out hover:text-purple-200">About</a> <a href="#" class="text-white transition duration-150 ease-in-out hover:text-purple-200">Contact</a> </nav> </div> </div> </header> <div class="flex flex-grow"> <aside class="w-72 bg-gray-100 scrollable-column"> <div class="p-6"> <h2 class="mb-4 text-xl font-semibold text-gray-800">Directories</h2> {#each item in dirs} <div class="mb-3"> <a href="{item.link}" class="font-medium text-indigo-600 transition duration-150 ease-in-out hover:text-indigo-800">{item.name}</a> </div> {/each} </div> </aside> <main class="flex-grow bg-white scrollable-column"> <div class="p-6 md:p-8"> {#each item in files} <div class="space-y-4"> <div class="flex flex-col sm:flex-row border-b-2 border-gray-200 pb-4"> <div class="w-full sm:w-[150px] h-[150px] border-2 border-black flex items-center justify-center overflow-hidden mb-4 sm:mb-0 flex-shrink-0"> <a href="{item.link}"> <img src="{item.image}" alt="thumbnail" class="w-full h-full object-cover"> </a> </div> <div class="flex-grow pt-2 sm:pl-4"> <h3 class="mb-2 text-xl font-semibold"> <a href="{item.link}" class="text-indigo-600 transition duration-150 ease-in-out hover:text-indigo-800">{item.name}</a> </h3> <p class="text-black text-sm -mt-2 mb-2">{item.date}</p> <p class="text-gray-600 text-lg">{item.summery}</p> </div> </div> </div> {/each} </div> </main> </div> <footer class="bg-gray-800 text-white"> <div class="container mx-auto px-4 py-8"> <div class="flex flex-col items-center justify-between md:flex-row"> <div class="mb-4 text-2xl font-semibold md:mb-0">Footer</div> <div class="flex space-x-4"> <a href="#" class="transition duration-150 ease-in-out hover:text-purple-300">Privacy</a> <a href="#" class="transition duration-150 ease-in-out hover:text-purple-300">Terms</a> <a href="#" class="transition duration-150 ease-in-out hover:text-purple-300">Contact</a> </div> </div> </div> </footer> {#include footer.html} '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php