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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`http:\/\/.*?\.pdf`) var str = `omberg. Retrieved September 3, 2010. Jump up ^ Bloomberg August 4, 2010 article. Jump up ^ Lauerman, John (April 2, 2014). "Apollo Falls as Education Department Demands Records". Bloomberg News. Retrieved May 1, 2014. Jump up ^ "Why Recent Criticism of the University of Phoenix is Unjustified, Rhonda P. Urban, Ementor, ezine by Warsaw School of Economics". E-mentor.edu.pl. Retrieved September 3, 2010. Jump up ^ "University of Phoenix 2007 Fact Book". Phoenix.edu. Retrieved September 3, 2010. Jump up ^ "U. of Phoenix Says Test Scores Vindicate Its Academic Model, Chronicle of Higher Education, BLUMENSTYK June 13, 2008" (PDF). Upxnewsroom.com. Retrieved September 3, 2010. Jump up ^ "University of Phoenix Ranks #1 in Graduating Master's Degree Students from Underrepresented Populations, Hispanic PR Wire". Hispanicprwire.com. July 18, 2007. Retrieved September 3, 2010. Jump up ^ Nealy, Michael (August 20, 2009). "Pride and Peril: Historically Black Colleges and Universities". Diverse – Issues in Higher Education. Retrieved September 25, 2009. Jump up ^ Jennifer H. Svan. "DOD renews contracts with four schools, drops University of Phoenix – News". Stripes. Retrieved October 5, 2013. Jump up ^ University of Phoenix Faculty Overview. Retrieved February 17, 2008. Jump up ^ "Supporting E-Learning at the University of Phoenix" (PDF). Retrieved September 3, 2010. ^ Jump up to: a b "Faculty". phoenix.edu. Jump up ^ "Search Results". Adjunct Project. Jump up ^ "Howard Schmidt, Cybersecurity 'Czar': Who Is He?". The Christian Science Monitor. Retrieved December 29, 2009. Jump up ^ Adams, Marilyn (February 5, 2008). "Events, Drive Keep DOT Chief in the Spotlight". USA Today. Retrieved September 3, 2010.http://somethink.pdf Jump up ^ "Brad L. Dee". Utah House of Representatives. Retrieved December 15, 2010. Jump up ^ United States Navy Biography U.S. Navy Web Site. Retrieved March 13, 2008. Jump up ^ "Mayor Bill White Announces Police Chief Nominee". City of Houston. February 27, http://RetrievedDecember.pdf 15, 2010. Jump up ^ "Christina Brown". MSNBC. 2010. Retrieved December 15, 2010. Jump up ^ The Big Executive? Shaq masters MBA MSNBC Web Site. Retrieved February 12, 2008. Jump up ^ Los Angeles Sparks Lisa Leslie Receives her Masters at University of Phoenix WireImage Website. Retrieved March 20, 2009. Jump up ^ "Michael Russell completes undergrad program from University of Phoenix". Tennisworldusa.org. January 15, 2012. Retrieved November 11, 2013.` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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 Golang, please visit: https://golang.org/pkg/regexp/