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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)^(?<type>(?:ci-|cloud-)?[^-]+)[_-](?<version>\d+\.\d+\.\d+)(?<alpha>[-+]alpha)?(?:-(?<date>\d{8}))?[-+](?:(?<build>\d+).(?<builddate>\d{8}))?(?:[.-]?(?<sha>[A-Fa-f0-9]+(?:[.-]\d+)?))?(?:\.(?<arch>.+))?\.(?<fmt>.{3})`) var str = `cloud-csm-6.4.13-20210927-89fa91ca.lnx.x86_64.zip cams-7.2.4+4.20211216.zip cams-7.2.4-alpha+4.20211216.zip cca-6.4.23+753.20211216.193a0386-1.noarch.rpm cca-6.4.23+alpha+753.20211216.193a0386-1.noarch.rpm cca-6.4.23-alpha+753.20211216.193a0386.zip cca_6.4.23+753.20211216.193a0386-1_all.deb ci-j2ee-6.4.23+790.20211216.193a0386.zip ci-j2ee-6.4.23-alpha+790.20211216.193a0386.zip ci-server-6.4.23+790.20211216.193a0386.zip ci-server-6.4.23-alpha+790.20211216.193a0386.zip cloud-ci-7.1.15+90.20210119.46eef7d3-1.noarch.rpm cloud-ci-7.2.4+247.20211216.eba3915b.noarch.zip cloud-ci-7.2.4+alpha+247.20211216.eba3915b-1.noarch.RPM cloud-ci-7.2.4-alpha+247.20211216.eba3915b.noarch.zip cloud-cm-7.2.4+246.20211216.eba3915b-1.noarch.rpm cloud-cm-7.2.4+246.20211216.eba3915b.noarch.zip cloud-cm-7.2.4+alpha+246.20211216.eba3915b-1.noarch.rpm cloud-cm-7.2.4-alpha+246.20211216.eba3915b.noarch.zip cloud-csd-7.2.4+241.20211216.eba3915b-1.x86_64.rpm cloud-csd-7.2.4+241.20211216.eba3915b.1-sym-x86_64.rpm cloud-csd-7.2.4+241.20211216.eba3915b.lnx.x86_64.zip cloud-csd-7.2.4+241.20211216.eba3915b.sym.lnx.x86_64.zip cloud-csd-7.2.4+alpha+241.20211216.eba3915b-1.x86_64.rpm cloud-csd-7.2.4+alpha+241.20211216.eba3915b.1-sym-x86_64.rpm cloud-csd-7.2.4-alpha+241.20211216.eba3915b.lnx.x86_64.zip cloud-csd-7.2.4-alpha+241.20211216.eba3915b.sym.lnx.x86_64.zip cloud-csm-6.4.13-20210927-89fa91ca.lnx.x86_64.zip cloud-csm-6.4.13-20210927-89fa91ca.win.x86.zip cloud-cst-7.2.4+241.20211216.eba3915b-1.x86_64.rpm cloud-cst-7.2.4+241.20211216.eba3915b.1-sym-x86_64.rpm cloud-cst-7.2.4+241.20211216.eba3915b.lnx.x86_64.zip cloud-cst-7.2.4+241.20211216.eba3915b.sym.lnx.x86_64.zip cloud-cst-7.2.4+alpha+241.20211216.eba3915b-1.x86_64.rpm cloud-cst-7.2.4+alpha+241.20211216.eba3915b.1-sym-x86_64.rpm cloud-cst-7.2.4-alpha+241.20211216.eba3915b.lnx.x86_64.zip cloud-cst-7.2.4-alpha+241.20211216.eba3915b.sym.lnx.x86_64.zip cloud-parts-7.2.4-20211216.zip cloud-parts-7.2.4-alpha-20211216.zip cloud-xds-6.4.6-20211101-4b76a168.lnx.x86.zip cloud-xds-6.4.6-20211101-4b76a168.win.x86.zip cm-6.4.23+798.20211216.193a0386-1.noarch.rpm cm-6.4.23+alpha+798.20211216.193a0386-1.noarch.rpm cm-6.4.23-alpha+798.20211216.193a0386.zip cm_6.4.23+798.20211216.193a0386-1_all.deb cm_6.4.23+alpha+798.20211216.193a0386-1_all.deb csm-6.4.13-20210927-89fa91ca.lnx.x86_64.tar csm-6.4.13-20210927-89fa91ca.win.x86.zip dbconfig-7.2.4+231.20211216.eba3915b.zip dbconfig-7.2.4-alpha+231.20211216.eba3915b.zip xds-6.4.6-20211101-4b76a168.lnx.x86.tar xds-6.4.6-20211101-4b76a168.win.x86.zip` 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/