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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

`
`
g

Test String

Substitution

Processing...

Code Generator

Generated Code

# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression. sed -E 's/(?|(\[[\"]?.+?[\"]?\])(=>)\R\s*|(?<=\(0\) )(\{)\R\s*(\}))/\1 \2/g;t' <<< "object(Symfony\Component\HttpFoundation\Request)#250 (21) { [\"attributes\"]=> object(Symfony\Component\HttpFoundation\ParameterBag)#253 (1) { [\"parameters\":protected]=> array(5) { [\"_controller\"]=> object(Closure)#239 (2) { [\"static\"]=> array(1) { [\"app\"]=> object(Silex\Application)#14 (8) { [\"providers\":protected]=> array(5) { [0]=> object(Silex\Provider\HttpKernelServiceProvider)#17 (0) { } [1]=> object(Silex\Provider\RoutingServiceProvider)#26 (0) { } [2]=> object(Silex\Provider\ExceptionHandlerServiceProvider)#36 (0) { } [3]=> object(Silex\Provider\TwigServiceProvider)#38 (0) { } [4]=> object(Euskadi31\Silex\Provider\CorsServiceProvider)#54 (0) { } } [\"booted\":protected]=> bool(true) [\"values\":\"Pimple\Container\":private]=> array(37) { [\"request.http_port\"]=> int(80) [\"request.https_port\"]=> int(443) [\"debug\"]=> bool(true) [\"charset\"]=> string(5) \"UTF-8\" [\"logger\"]=> NULL [\"resolver\"]=> object(Symfony\Component\HttpKernel\Controller\ControllerResolver)#307 (1) { [\"logger\":\"Symfony\Component\HttpKernel\Controller\ControllerResolver\":private]=> NULL } [\"argument_metadata_factory\"]=> object(Symfony\Component\HttpKernel\ControllerMetadata\ArgumentMetadataFactory)#301 (0) { } [\"argument_value_resolvers\"]=> array(5) { [0]=> object(Silex\AppArgumentValueResolver)#298 (1) { [\"app\":\"Silex\AppArgumentValueResolver\":private]=> *RECURSION* } [1]=> object(Symfony\Component\HttpKernel\Controller\ArgumentResolver\RequestAttributeValueResolver)#295 (0) { } [2]=> object(Symfony\Component\HttpKernel\Controller\ArgumentResolver\RequestValueResolver)#292 (0) { } [3]=> object(Symfony\Component\HttpKernel\Controller\ArgumentResolver\DefaultValueResolver)#289 (0) { } [4]=> object(Symfony\Component\HttpKernel\Controller\ArgumentResolver\VariadicValueResolver)#286 (0) { } }"

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 SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html