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

Code Generator

Language

Generated Code

const regex = /^module.(?<module_name>.*)\.(?<module_subname>.*)\.(?<module_item>[a-z|\_|\-|\[|\]|0-9]*[a-z|\.|\[|0-9\]])\:\ (?<action_type>[A-Z|a-z|\ ]*(?<action_status>\.\.\.\ |complete))|\ after\ (?<complete_time>[0-9]*s)|\((?<elapsed_time>[0-9]*s)\ elapsed\)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^module.(?<module_name>.*)\\.(?<module_subname>.*)\\.(?<module_item>[a-z|\\_|\\-|\\[|\\]|0-9]*[a-z|\\.|\\[|0-9\\]])\\:\\ (?<action_type>[A-Z|a-z|\\ ]*(?<action_status>\\.\\.\\.\\ |complete))|\\ after\\ (?<complete_time>[0-9]*s)|\\((?<elapsed_time>[0-9]*s)\\ elapsed\\)', 'gm') const str = `module.indexer.aws_autoscaling_group.indexer.0: Still creating... (30s elapsed) module.indexer.aws_autoscaling_group.indexer.2: Still creating... (30s elapsed) module.indexer.aws_autoscaling_group.indexer.1: Still creating... (30s elapsed) module.indexer.aws_autoscaling_group.indexer.0: Still creating... (40s elapsed) module.indexer.aws_autoscaling_group.indexer.2: Still creating... (40s elapsed) module.indexer.aws_autoscaling_group.indexer.1: Still creating... (40s elapsed) module.cluster_master.aws_autoscaling_group.cluster_master: Creation complete after 40s (ID: sre-sandbox - cluster-master) module.sh1.aws_autoscaling_group.search_head: Creation complete after 40s (ID: sh1 - sre-sandbox - search-head) module.cluster_master.aws_autoscaling_group.cluster_master: Creation complete after 40s (ID: sre-sandbox - cluster-master) module.sh1.aws_autoscaling_group.search_head: Creation complete after 40s (ID: sh1 - sre-sandbox - search-head) module.indexer.aws_autoscaling_group.indexer[0]: Creation complete after 41s (ID: sre-sandbox - indexer - subnet-78aba033) module.indexer.aws_autoscaling_group.indexer[1]: Creation complete after 41s (ID: sre-sandbox - indexer - subnet-08397f55) module.kms_key.aws_kms_key.stack_key: Destruction complete after 22s module.iam_profile.aws_iam_role.stack_iam_role: Destruction complete after 1s module.indexer.null_resource.indexer_asg[1]: Destruction complete after 0s module.indexer.null_resource.indexer_asg[2]: Destruction complete after 0s module.security_groups.aws_security_group_rule.public_search_head_vault: Destruction complete after 1s module.security_groups.aws_security_group_rule.private_sg_self_rule_out[2]: Destruction complete after 1s module.security_groups.aws_security_group_rule.private_sg_ldap_outbound[0]: Destroying... (ID: sgrule-1706144597) module.indexer.aws_autoscaling_attachment.hec[1]: Destroying... (ID: sre-sandbox - indexer - subnet-08397f55-20190901000149529200000006) module.security_groups.aws_security_group_rule.private_sg_port443: Destroying... (ID: sgrule-2181904703) module.security_groups.aws_security_group_rule.private_sg_self_rule_out[3]: Destruction complete after 1s module.indexer.aws_ssm_parameter.facts: Destroying... (ID: /dev/facts/stack/sre-sandbox/indexer) module.indexer.dyn_node.inputs-dns[4]: Destruction complete after 6s module.security_groups.aws_security_group_rule.indexer_self[1]: Destroying... (ID: sgrule-2553743418) module.indexer.aws_ssm_parameter.facts: Destruction complete after 0s module.indexer.aws_autoscaling_attachment.hec[1]: Destruction complete after 1s module.security_groups.aws_security_group_rule.private_sg_self_rule[0]: Destroying... (ID: sgrule-262603171) module.sh1.aws_autoscaling_group.search_head: Destroying... (ID: sh1 - sre-sandbox - search-head) `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions