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

/
/
gmx

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?<key>\w+)= (?<value> [^"\s]+(?!\S) | \\"(?:[^\\"]|\\{3}")*\\" )`) var str = `level=info ts=2023-10-20T14:30:48.716410806Z caller=metrics.go:159 component=frontend org_id=fake traceID=58290ebda8d79180 latency=fast query=\"sum by (level) (count_over_time({k8s_namespace=\\\"ingress-nginx\\\"} |= \`\`[1s]))\" query_hash=110010092 query_type=metric range_type=range length=15m0.001s start_delta=15m0.833402507s end_delta=832.40267ms step=1s duration=61.999532ms status=200 limit=1000 returned_lines=0 throughput=4.2MB total_bytes=260kB total_bytes_structured_metadata=0B lines_per_second=4209 total_lines=261 post_filter_lines=261 total_entries=1 store_chunks_download_time=0s queue_time=819.962996ms splits=2 shards=32 cache_chunk_req=0 cache_chunk_hit=0 cache_chunk_bytes_stored=0 cache_chunk_bytes_fetched=0 cache_chunk_download_time=0s cache_index_req=0 cache_index_hit=0 cache_index_download_time=0s cache_stats_results_req=0 cache_stats_results_hit=0 cache_stats_results_download_time=0s cache_result_req=0 cache_result_hit=0 cache_result_download_time=0s source=logvolhist` 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/