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

r"
"
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"/\*/?(\n|[^/]|[^*]/)*\*/" test_str = ("/*********************\n" " * test\n" " * multiline\n" " */\n\n" "/* next表示を半透明でなくする (カクつき防止のテスト) */\n" "#content-tips-wrap {\n" " opacity: 1!important;\n" "}\n\n\n" "/* path /_ct/* */\n\n" "/* なるほどねー */\n\n" "/***** compact footer ****/\n" "@import url('/static/dinoportal/custom/content-compactfooter.css');\n\n" "/***** Read All *****/\n" "@import url('/static/dinoportal/custom/content-addmore.css');\n" "@requirejs: url('/static/dinoportal/custom/content-addmore.js');\n\n" "/* endpath */\n\n" "/* ヘッダメニューを常にモバイルと同じにする */\n" "@import url('/static/dinoportal/custom/header-menu-always-mobile.css');\n\n" "/* メニューフィードの写真・カードの先頭を大きく */\n" "@import url('/static/dinoportal/custom/menufeed-big-leading.css');\n\n" "/* 写真・カードのフィードをモバイルで2列表示 */\n" "@import url('/static/dinoportal/custom/feed-card-mobile-2cols.css');\n\n" "/* サイドバーを左に */\n" "@import url('/static/dinoportal/custom/sidebar-left.css');\n\n" "/* サイドバーの要素をブロック分け */\n" "@import url('/static/dinoportal/custom/sidebar-separate.css');\n\n" "/* コンテンツカバー画像をぼかす */\n" "/* @import url('/static/dinoportal/custom/content-cover-blur.css'); */\n\n" "/* 各種色設定 (LESS記法) */\n" "@import url('/static/dinoportal/custom/colors.less');\n" "/* ベース */\n" "@colors-base: hsl(207, 40%, 15%); /* 文字 */\n" "@colors-base-bg: white; /* 背景 */\n" "/* 箱囲み要素 */\n" "@colors-base-box: @colors-base; /* 文字 */\n" "@colors-base-box-bg: fade(@colors-base, 12%); /* 背景 */\n" "/* ヘッダ */\n" "@colors-header: #eee; /* 文字 */\n" "@colors-header-bg: black; /* 背景 */\n" "@colors-header-shadow: black; /* ヘッダ下線 */\n" "/* ヘッダメニュー */\n" "@colors-header-menu: @colors-header; /* 文字 */\n" "@colors-header-menu-bg: @colors-header-bg; /* 背景 */\n" "/* ヘッダメニュー(選択中メニュー) */\n" "@colors-header-menu-active: white; /* 文字 */\n" "@colors-header-menu-active-bg: transparent; /* 背景 */\n" "@colors-header-menu-active-mark: hsl(0,100%,35%); /* 下線 */\n" "/* ウィジェット */\n" "@colors-widget: @colors-base-box; /* 文字 */\n" "@colors-widget-bg: @colors-base-box-bg; /* 背景 */\n" "/* タイトル系 */\n" "@colors-menufeed-title: black; /* メニューフィードのブロックタイトル */\n" "@colors-contents-title: @colors-base; /* フィードのコンテンツタイトル */\n" "/* 写真・カード型フィード */\n" "@colors-cards-bg: #eee; /* 写真・カード型フィードの背景 */\n" "/* コンテンツ */\n" "@colors-content-heading: @colors-base; /* 見出し */\n" "@colors-content-heading-decoration: @colors-base; /* 見出し装飾色 */\n" "@colors-content-subheading: @colors-base; /* 小見出し */\n" "@colors-content-subheading-decoration: @colors-base; /* 小見出し装飾色 */\n" "@colors-content-body-link: @colors-base; /* コンテンツ内リンク */\n" "@colors-content-body-link-active: @colors-base; /* コンテンツ内リンク(アクティブ/ホバー) */\n" "@colors-content-quote: @colors-base-box; /* 引用ボックス(文字) */\n" "@colors-content-quote-bg: @colors-base-box-bg; /* 引用ボックス(背景) */\n" "@colors-content-box: @colors-base-box; /* 箱囲み段落(文字) */\n" "@colors-content-box-bg: @colors-base-box-bg; /* 箱囲み段落(背景) */\n\n\n" "/* モバイルでメニューフィードサイドバーの.widget要素を最下部にまとめる */\n" "/* @adjustwidgets: ~`window._adjustwidgets = {start:10000, step:0}`; */\n\n\n" "/* モバイル、メニューフィード、通常リスト型表示の後続要素のタイトルをボールドに */\n" "@media (max-width:767px) {\n" " #newsfeed .newsfeed-block.newsfeed-all-display-type-list .wfcontent.not-has-display-type .content-title {\n" " font-weight:bold;\n" " font-size:110%;\n" " }\n" "}\n\n" "/* 記事小見出し */\n" ".article > h3 {\n" " border:1px solid hsl(171, 80%, 45%);\n" " padding:.4em .5em .3em 1.5em;\n" " position:relative;\n" "}\n" ".article > h3:before {\n" " content:'';\n" " position:absolute;\n" " top:.4em;\n" " left:.4em;\n" " bottom:.4em;\n" " width:.75em;\n" " background:hsl(171, 80%, 45%);\n" "}\n\n" ".article > h4 {\n" " font-size:100%;\n" " border-left:.2em solid hsl(171, 80%, 45%);\n" " padding-left:.4em;\n" "}\n\n" "/****** banners-2col debug *******/\n" ".banners-2col { position:relative; }\n" ".banners-2col > a > img {\n" " display:block;\n" " width:100%;\n" " margin:0;\n" " padding:0;\n" "}\n" ".banners-2col > a {\n" " margin:0; padding:0;\n" " display:inline-block;\n" " position:relative;\n" " width:49%;\n" " width:-webkit-calc( 50% - 2px );\n" " width:calc( 50% - 2px );\n" " width:~\"calc( 50% - 2px )\"; /* for LESS */\n" " display:inline-block;\n" " vertical-align:top;\n" "}\n" ".banners-2col > a:hover {\n" " text-decoration:none;\n" "}\n" ".banners-2col > a:nth-child(2n+1) {\n" " margin-right:2%;\n" " margin-right:4px;\n" "}\n" ".banners-2col > a:nth-child(n+3) {\n" " margin-top:4px;\n" "}") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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