Regular Expressions 101

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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

Language

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/^Hi.*Page (\d+).*\n(.*)/> $2 [@attia:2023 p.$1]\n/gm;t' <<< "Notes and highlights for Outlive Attia MD, Peter Part I Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 10 · Location 150 In 1900 , life expectancy hovered somewhere south of age fifty , and most people were likely to die from “ fast ” causes : accidents , injuries , and infectious diseases of various kinds . Since then , slow death has supplanted fast death . The majority of people reading this book can expect to die somewhere in their seventies or eighties , give or take , and almost all from “ slow ” causes . Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 10 · Location 154 Four Horsemen : heart disease , cancer , neurodegenerative disease , or type 2 diabetes and related metabolic dysfunction . Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 10 · Location 155 we must understand and confront these causes of slow death . Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 10 · Location 158 Healthspan is typically defined as the period of life when we are free from disability or disease , Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 14 · Location 215 It is absurd and harmful to treat this disease like a cold or a broken bone , where you either have it or you don’t ; it’s not binary . Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 14 · Location 218 Changing that mindset must be our first step in attacking slow death . We want to delay or prevent these conditions so that we can live longer without disease , rather than lingering with disease . Highlight (yellow) - Chapter 1: The Long Game: From Fast Death to Slow Death > Page 17 · Location 270 Exercise is by far the most potent longevity “ drug . ” No other intervention does nearly as much to prolong our lifespan and preserve our cognitive and physical function ."

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