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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?:implements|new|@var|extends)\s*(?P<fullNamespace>\\[A-Za-z]+|[A-Za-z]+?(?:\\(?P<class>[A-Za-z]+))+)") test_str = ("<?php\n" "declare(strict_types=1);\n\n" "namespace Jerry\\QueryBuilder\\Builder;\n\n" "use Jerry\\Interfaces\\QueryInterface;\n" "use Jerry\\Interfaces\\Statements\\FilterInterface;\n" "use Jerry\\QueryBuilder\\Statements\\Filters\\Where;\n\n" "class Builder implements Jerry\\Interfaces\\BuilderInterface\\BuilderInterface extends Jerry\\Base\\Stuff\n" "{\n" " /** @var Jerry\\Interfaces\\ConnectorInterface\\Foo */\n" " private $connection;\n\n" " /** @var \\PDOStatement */\n" " private $statement;\n\n" " /** @var string */\n" " private $sql;\n\n" " /** @var QueryInterface */\n" " private $query;\n\n" " /** @var string */\n" " private $filterSql;\n\n" " /** @var array */\n" " private $values;\n\n" " public function __construct(Jerry\\Interfaces\\ConnectorInterface $connection)\n" " {\n" " $this->connection = $connection;\n" " }\n\n" " public function getResults(QueryInterface $query): array\n" " {\n" " $this->query = $query;\n" " return [];\n" " }\n\n" " private function buildSql(): void\n" " {\n" " }\n\n" " private function buildFilters(array $filters = [], string $filterSql = \"\"): void\n" " {\n" " if (! count($filters)) {\n" " $filters = $this->query->getFilters();\n" " }\n\n" " $iterator = new \\ArrayIterator($filters);\n\n" " while ($iterator->valid()) {\n" " $filter = $iterator->current();\n\n" " $iterator->next();\n" " }\n" " /** @var FilterInterface $filter */\n" " foreach ($filters as $key => $filter) {\n" " unset($filters[$key]);\n\n" " if ($filter instanceof Where) {\n" " // WHERE foo = bar\n" " $filterSql .= \"WHERE ? ? ?\";\n" " }\n" " }\n" " }\n\n" " public function getConnection(): ConnectorInterface\n" " {\n" " $foo = new Jerry\\Interfaces\\ConnectorInterface();\n" " return $this->connection;\n" " }\n\n" " public function setConnection(ConnectorInterface $connection): void\n" " {\n" " $this->connection = $connection;\n" " }\n\n" " public function getSql(): string\n" " {\n" " return $this->sql;\n" " }\n" "}") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html