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

Language

Generated Code

re = /((^0)\s+|(^1)\s+|(^2)\s+|(^3)\s+|(^4)\s+|(^5)\s+)((((.{4})(.+)))|((.{4})))/m str = '0 @I0066@ INDI 1 NAME Joan Adrienne /Hatch/ 2 GIVN Joan Adrienne 2 SURN Hatch 2 SOUR @S0045@ 3 DATA 4 TEXT Birth date: 30 May 1935 Birth place: Hennepin, Minnesota 2 SOUR @S0131@ 3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A 3 DATA 4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot 5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis 5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch 3 NOTE @N0121@ 2 SOUR @S0635@ 3 DATA 4 TEXT Marriage date: 29 Dec 1953 Marriage place: Cook County, IL 1 SEX F 1 BIRT 2 DATE 30 MAY 1935 2 PLAC Minneapolis, Hennepin, Minnesota, USA 2 SOUR @S0045@ 3 DATA 4 TEXT Birth date: 30 May 1935 Birth place: Hennepin, Minnesota 2 SOUR @S0131@ 3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A 3 DATA 4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot 5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis 5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch 3 NOTE @N0125@ 1 DEAT 2 DATE 14 DEC 1989 2 PLAC Nyack, Rockland, New York, USA 1 RESI 2 DATE 1 APR 1940 2 PLAC Faribault, Rice, Minnesota, USA 2 SOUR @S0131@ 3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A 3 DATA 4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot 5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis 5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch 3 NOTE @N0127@ 1 RESI 2 DATE 1 APR 1940 2 PLAC Faribault, Rice, Minnesota, USA 2 SOUR @S0131@ 3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A 3 DATA 4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot 5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis 5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch 3 NOTE @N0129@ 1 FAMC @F1196@ 1 FAMS @F0129@ 1 FAMS @F0260@ 1 CHAN 2 DATE 31 MAR 2017 3 TIME 22:03:40' subst = '\\n $1 | $2 | $3 | $4 | $5 | $6 | $7 | $8 | $9 | $10 | $11 | $12 | $13 | $14 | |' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html