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

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)^@(.*?){(.*?),((.|\n)*?)+(}}|\n})+$`) var str = `@inproceedings{martens2010deep, title={Deep learning via Hessian-free optimization}, author={Martens, James}, booktitle={Proceedings of the 27th International Conference on Machine Learning (ICML-10)}, pages={735--742}, year={2010} } @article-journal{AAA, url = {http://www.example.com}, year = {2016}, month = {}, publisher = {Elsevier}, journal = {{AAA Journal}}, author = {Austin Anderson and Austin Arnold}, title = {{Nothing To See Here}}, } @article-journal{ZZZ, url = {http://www.example.com}, year = {2016}, month = {}, publisher = {Elsevier}, journal = {{ZZZ Journal}}, author = {Austin Zyzygy}, title = {{Moving On Up}}, } @article-journal{InstMed2001, url = {http://www.ncbi.nlm.nih.gov/pubmed/25057539}, year = {2001}, month = {}, publisher = {{National Academy of Sciences}}, doi = {10.17226/10027}, volume = {}, number = {}, pages = {}, pmid = {25057539}, pmcid = {}, journal = {{}}, author = {{National Academy of Sciences}}, title = {{Crossing the Quality Chasm: A New Health System for the 21st Century}}, } @article-journal{Wallace2013, url = {http://apt.rcpsych.org/content/19/4/250}, year = {2013}, month = {July}, publisher = {{Royal College of Psychiatrists}}, doi = {10.1192/apt.bp.112.010389}, volume = {19}, number = {4}, pages = {250-258}, journal = {{BJPsych Advances}}, author = {John Wallace}, title = {{Lost in translation: transferring knowledge from research to clinical practice}}, } @article-journal{Glasziou2005, url = {http://ebn.bmj.com/content/8/2/36.full}, year = {2005}, month = {}, publisher = {{British Medical Journal}}, doi = {10.1136/ebn.8.2.36}, volume = {8}, number = {}, pages = {36-38}, journal = {{Evidence Based Nursing}}, author = {Paul Glasziou and Brian Haynes}, title = {{The paths from research to improved health outcomes}}, } @article-journal{Glasziou2011, url = {http://pmj.bmj.com/content/early/2011/06/29/pgmj.2010.116012.full.html}, year = {2011}, month = {June}, publisher = {{British Medical Journal}}, doi = {10.1136/pgmj.2010.116012}, volume = {}, number = {}, pages = {}, pmid = {}, pmcid = {}, journal = {{Postgraduate Medicine Journal}}, author = {Sharon Mickan and Amanda Burls and Paul Glasziou}, title = {{Patterns of 'leakage' in the utilisation of clinical guidelines: a systematic review}}, } ` var substitution = "{\"id\":\"${2}\",\"type\":${1},\"content\":[{${3}]}}" fmt.Println(re.ReplaceAllString(str, 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 Golang, please visit: https://golang.org/pkg/regexp/