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

/
/
g

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`location_1_coordinates\=\"\[(?<longitude>[-\.\d]*)\, (?<latitude>[-\.\d]*)`) var str = `01/28/2017 23:50:00 -0500, search_name="Update Baltimore Incidents", search_now=1486130400.000, info_max_time=1486130400.000, info_search_time=1486130401.183, crimecode=3AF, crimedate="2017-01-28T00:00:00.000", crimetime="23:50:00", ctime="2017-01-28T23:50:00", description="ROBBERY - STREET", district=WESTERN, inside_outside=O, location="2700 PENNSYLVANIA AVE", location_1="{u'coordinates': [-76.64548, 39.31253], u'type': u'Point'}", location_1_coordinates="[-76.64548, 39.31253]", location_1_type=Point, neighborhood="Penn North", post=733, premise=STREET, total_incidents=1, weapon=FIREARM` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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/