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

/
/
gm

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/^([ \t]*)import [*] as (\w+) from (?:(['])((?:(?:\.)+|[^\n\r'\\]+)+)[']|(["])((?:(?:\.)+|[^\n\r'\\]+)+)["])/$1import $2 from $3$5$6$4$3$5/gm;t' <<< "import * as Atblock from \"./atblock\" import * as Atrule from \"./atrule\" import * as Supports from \"./supports\" import * as Node from './node'; import * as Root from './root' import Null from './null' import * as Each from './each' import * as If from './if' import * as Call from './call' import * as UnaryOp from './unaryop' import * as BinOp from './binop' import * as Ternary from './ternary' import * as Block from './block' import * as Unit from './unit' import * as String from './string' import * as HSLA from './hsla' import * as RGBA from './rgba' import * as Ident from './ident' import * as Group from './group' import * as Literal from './literal' import * as Boolean from './boolean' import * as Return from './return' import * as Media from './media' import * as QueryList from './query-list' import * as Query from './query' import * as Feature from './feature' import * as Params from './params' import * as Comment from './comment' import * as Keyframes from './keyframes' import * as Member from './member' import * as Charset from './charset' import * as Namespace from './namespace' import * as Import from './import' import * as Extend from './extend' import * as Object from './object' import * as Function from './function' import * as Property from './property' import * as Selector from './selector' import * as Expression from './expression' import * as Arguments from './arguments' import * as Atblock from './atblock' import * as Atrule from './atrule' import * as Supports from './supports' "

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