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"(?<m>\$(?:[a-z[:digit:]]*-*)*)", flags=re.MULTILINE) test_str = ("$application-background: rgba(81, 99, 120, 0.1);\n" "$application-background-light: #ffffff;\n\n" "$primary13-light: #00a6ff; // rgba(0, 166, 255, 1)\n" "$primary-light-accent: #1f95f8;\n" "$primary-lighter: #99dcff;\n" "$primary-dark: #36436b; // rgba(54, 67, 107, 1)\n" "$primary-darker: #2b3555;\n" "$primary-darkest: #191f32;\n" "$secondary-light: #008aff;\n" "$tertiary-light: #4f5bff;\n" "$quaternary-light: #27358c;\n" "$sub-accent1: #00ea42;\n" "$sub-accent2: #bedb00;\n" "$sub-accent3: #ffb428;\n\n" "$widget-light: #f3f4f6;\n" "$widget-lightest: #ffffff;\n" "$widget-disabled-light: #ccc;\n" "$widget-disabled-lighter: #f9f9f9;\n" "$navbar-color-default: $widget-lightest;\n" "$navbar-light-color: #fafafa;\n" "$sidebar-background: #fafafa;\n" "$text-light: #516378;\n" "$text-lighter: #889aae;\n" "$text-lightest: #cccccc;\n" "$text-dark: #ffffff;\n" "$text-dark2: #efefef;\n" "$text-darker: #dedede;\n" "$text-disabled: $text-lightest;\n" "$text-placeholder-dark: $text-dark2;\n" "$text-navbar-bright: rgba(0, 0, 0, 0.9);\n" "$text-navbar-bright2: rgba(0, 0, 0, 0.4);\n" "$text-navbar-dark: rgba(255, 255, 255, 1);\n" "$text-navbar-dark2: rgba(255, 255, 255, 0.4);\n" "$border-light: #e8ebed;\n" "$border-dark: #ccc;\n" "$border-active: $text-light;\n" "$border-color-dark: #d9d9d9 $border-dark #b3b3b3;\n" "$warning: #ffa908;\n" "$trend-high: #ff3d79;\n" "$trend-low: #1e98ff;\n" "$trend-mid: $text-light;\n\n" "$list-item-selected: rgba(81, 99, 120, 0.2);\n" "$list-item-hover: rgba(81, 99, 120, 0.1);\n\n" "$poor: #ff7da5;\n" "$fair: #ffafc8;\n" "$average: #ffdfa4;\n" "$good: #a1d525;\n" "$excellent: #00d63d;\n\n\n" ":export {\n" " primaryDark: $primary-dark;\n" " primaryLight: $primary-light;\n" " secondaryLight: $secondary-light;\n" " tertiaryLight: $tertiary-light;\n" " quaternaryLight: $quaternary-light;\n" " subAccent1: $sub-accent1;\n" " subAccent2: $sub-accent2;\n" " subAccent3: $sub-accent3;\n" " poor: $poor;\n" " fair: $fair;\n" " average: $average;\n" " good: $good;\n" " excellent: $excellent;\n" "}\n\n\n" "$black: black;\n" "$black-10: rgba(0, 0, 0, .1);\n" "$black-15: rgba(0, 0, 0, .15);\n" "$black-20: rgba(0, 0, 0, .2);\n" "$black-30: rgba(0, 0, 0, .3);\n" "$black-40: rgba(0, 0, 0, .4);\n" "$darker: #152128;\n" "$darker-40: rgba(21, 32, 40, .4); // rgba($darker, .4)\n" "$darker-50: rgba(21, 32, 40, .5); // rgba($darker, .5)\n" "$darker-70: rgba(21, 32, 40, .7); // rgba($darker, .7)\n" "$darker-80: rgba(21, 32, 40, .8); // rgba($darker, .8)\n" "$darker-90: rgba(21, 32, 40, .9); // rgba($darker, .9)\n" "$dark-two-10: rgba(81, 99, 120, .1);\n" "$dark-two-20: rgba(81, 99, 120, .2);\n" "$dark: #516378;\n" "$dark-60: rgba(81, 99, 120, .6);\n" "$dark-10: rgba(81, 99, 120, .1); // rgba(80, 99, 120, .1) rgba(81, 99, 119, .1)\n" "$dark-15: rgba(81, 99, 120, .15);\n" "$dark-30: rgba(81, 99, 120, .3);\n" "$dark-20: rgba(81, 99, 120, .2); // rgba(80, 99, 120, .2) rgba(81, 99, 119, .2)\n" "$dark-40: rgba(81, 99, 120, .4);\n" "$dark-6: rgba(81, 99, 120, .06);\n" "$gray: #7C858C;\n" "$light: #98A7B3; // #97A7B4 #97A6B2\n" "$light-50: rgba(152, 166, 179, .5);\n" "$lighter: #E8EBED;\n" "$smooth-sky: #87D5FF;\n" "$sky: #00E2F5;\n" "$sky-20: rgba(0, 221, 244, .2);\n" "$magenta: #FF21A3;\n" "$magenta-10: rgba(255, 33, 163, .1);\n" "$yellow: #FFB000; // #FFA908\n" "$lemon: #EDED00;\n" "$spring: #4BFF6B;\n" "$green: #00D63D;\n" "$cobalt: #00A6FF;\n" "$cobalt-10: rgba(0, 195, 255, .1); // rgba(0, 165, 255, .1)\n" "$cobalt-20: rgba(0, 195, 255, .2);\n" "$blue: #4A4FEB;\n" "$purple: #9270FF;\n" "$navy: #1B1464;\n" "$snow: #F3F4F5; // #F2F2F2\n" "$snow-68: rgba(243, 244, 245, .68);\n" "$pale-grey-five: #F5F5F7;\n" "$snow-60: rgba(243, 244, 245, .6); // rgba(243, 243, 244, .6)\n" "$warm-grey-10: rgba(119, 119, 119, .1);\n" "$white: white;\n" "$white-30: rgba(255, 255, 255, .3);\n" "$white-50: rgba(255, 255, 255, .5);\n" "$white-70: rgba(255, 255, 255, .7);\n" "$midnight: #36436B;\n" "$midnight-hover: #2B3457;\n" "$dawn: #5B83FE;\n" "$dawn-hover: #4864CD;\n" "$periwinkle: #A98FFF;\n" "$pastel-purple: #B7A1FF;\n" "$carolina-blue: #87A5FF;\n" "$pastel-blue: #9DB5FE;\n" "$pale-grey: #EEF1F4;\n" "$warm-pink: #FF3D79;\n" "$warm-pink-darker: #e6376e;\n" "$warm-pink-darkest: #c22f5d;\n" "$warm-pink-15: rgba(255, 61, 121, .15);\n" "$pale-grey-two: #E8EBED;\n" "$pale-grey-two-50: rgba(232, 235, 237, .5);\n" "$pale-grey-two-30: rgba(232, 235, 237, .3);\n" "$pale-grey-two-70: rgba(232, 235, 237, .7);\n" "$pale-grey-two-20: rgba(232, 235, 237, .2);\n" "$pale-grey-two-10: rgba(232, 235, 237, .1);\n" "$pale-grey-three: #EAEFF4;\n" "$charcoal-grey: #2B2F35;\n" "$charcoal-grey-80: rgba(43, 47, 43, .8); // rgba(42, 47, 52, .8)\n" "$charcoal-grey-90: rgba(43, 47, 43, .9); // rgba(43, 47, 52, .9)\n" "$charocol-grey-30: rgba(43, 47, 53, .3);\n" "$silver: #DCE0E4; // #CFD2D4 #C9D0D5\n" "$silver-two: #D2DADF;\n" "$silver-three: #C9D0D5;\n" "$azure: #00A6FF;\n" "$azure-two: #0095E4;\n" "$azure-hover: #008AD4;\n" "$watermelon: #FF4168;\n" "$light-30: rgba(152, 166, 179, .3);\n" "$light-70: rgba(152, 166, 179, .7);\n" "$cerulean: #007DC0;\n" "$wheat: #FFD37E;\n" "$off-white-two: #FFF6E1;\n" "$pale-peach-two: #FFDEAD;\n" "$ice-blue: #ECF9FF;\n" "$pale-sky-blue: #B7E7FF;\n" "$slate: #516272;\n" "$bluey-grey: #97A6B2;\n" "$bluey-grey-two: #98A7B3;\n" "$bluey-grey-three: #A7B6C2;\n" "$slate-three: #405064;\n" "$slate-two: #404F5F;\n" "$silver-four: #DEE1E4;\n" "$silver-five: #D9DCDF;\n" "$coral-pink: #FF5771;\n" "$silver-six: #C0C9D0;\n" "$sky-blue: #5CC7FF;\n\n" ":export {\n" " dark: $dark;\n" " dark10: $dark-10;\n" " dark20: $dark-20;\n" "}\n\n" "// not registered in zeplin\n" "$warm-dark: #404F5F; // #435262\n" "$warm-dark-40: rgba(64, 79, 95, .4); // rgba(64, 80, 101, .4)\n" "$soft-sky: #8FD8FF;\n" "$charcoal-grey-two: #2F343A;\n" "$azure-three: #00C3FF;\n" "$deep-green: #00A02E;\n" "$sun-yellow: #F5E11F;\n" "$cadet-blue: #52689D;\n" "$greenblue: #00D175;\n" "$greenblue-two: #00B07F;\n" "$light-sky-blue: #CCF3FF;\n" "$event-header: #EDEFF0;\n\n" "// react table\n" "$tr-group-border: rgba(0, 0, 0, .05);\n\n" "// shop AB funnel page\n" "$resource-a: #7ab8fc;\n" "$resource-b: #86919f;\n\n" ":export {\n" " resourceA: $resource-a;\n" " resourceB: $resource-b;\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