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

/
/
gm

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)"PrivKey": "([a-zA-Z0-9_=\/-\\+]+)`) var str = ` { "API": { "HTTPHeaders": {} }, "Addresses": { "API": "/ip4/0.0.0.0/tcp/5001", "Announce": [], "Gateway": "/ip4/0.0.0.0/tcp/8080", "NoAnnounce": [], "Swarm": [ "/ip4/0.0.0.0/tcp/4001", "/ip6/::/tcp/4001" ] }, "Bootstrap": [ "/dnsaddr/bootstrap.libp2p.io/ipfs/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN", "/dnsaddr/bootstrap.libp2p.io/ipfs/QmQCU2EcMqAqQPR2i9bChDtGNJchTbq5TbXJJ16u19uLTa", "/dnsaddr/bootstrap.libp2p.io/ipfs/QmbLHAnMoJPWSCR5Zhtx6BHJX9KiKNN6tpvbUcqanj75Nb", "/dnsaddr/bootstrap.libp2p.io/ipfs/QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt", "/ip4/104.131.131.82/tcp/4001/ipfs/QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ", "/ip4/104.236.179.241/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM", "/ip4/128.199.219.111/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu", "/ip4/104.236.76.40/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64", "/ip4/178.62.158.247/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd", "/ip6/2604:a880:1:20::203:d001/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM", "/ip6/2400:6180:0:d0::151:6001/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu", "/ip6/2604:a880:800:10::4a:5001/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64", "/ip6/2a03:b0c0:0:1010::23:1001/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd" ], "Datastore": { "BloomFilterSize": 1048576, "GCPeriod": "1h", "HashOnRead": false, "Spec": { "child": { "path": "badgerds", "syncWrites": true, "truncate": true, "type": "badgerds" }, "prefix": "badger.datastore", "type": "measure" }, "StorageGCWatermark": 90, "StorageMax": "100GB" }, "Discovery": { "MDNS": { "Enabled": true, "Interval": 10 } }, "Experimental": { "FilestoreEnabled": false, "Libp2pStreamMounting": false, "P2pHttpProxy": false, "PreferTLS": false, "QUIC": false, "ShardingEnabled": false, "UrlstoreEnabled": false }, "Gateway": { "APICommands": [], "HTTPHeaders": { "Access-Control-Allow-Headers": [ "X-Requested-With", "Range", "User-Agent" ], "Access-Control-Allow-Methods": [ "GET" ], "Access-Control-Allow-Origin": [ "*" ] }, "NoFetch": false, "PathPrefixes": [], "RootRedirect": "", "Writable": false }, "Identity": { "PeerID": "Qme2joV44qiG38Q7YaEti6N1QMiM6XujXairxgJqJB9DeT", "PrivKey": "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" }, "Ipns": { "RecordLifetime": "", "RepublishPeriod": "", "ResolveCacheSize": 128 }, "Mounts": { "FuseAllowOther": false, "IPFS": "/ipfs", "IPNS": "/ipns" }, "Pubsub": { "DisableSigning": false, "Router": "", "StrictSignatureVerification": false }, "Reprovider": { "Interval": "12h", "Strategy": "all" }, "Routing": { "Type": "dht" }, "Swarm": { "AddrFilters": null, "ConnMgr": { "GracePeriod": "20s", "HighWater": 2000, "LowWater": 600, "Type": "basic" }, "DisableBandwidthMetrics": false, "DisableNatPortMap": false, "DisableRelay": false, "EnableAutoNATService": false, "EnableAutoRelay": false, "EnableRelayHop": false } }` 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/