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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
Processing...

Test String

Code Generator

Generated Code

import re regex = re.compile(r"(?:Solution:)?\s*(?:\d+\. )?(.+?)(?=\n(?:Solution:|\d+\. )|\Z)", flags=re.MULTILINE | re.DOTALL) test_str = ("Solution: To create a Nextflow configuration file, follow these steps:\n\n" "1. Create a new file named `nextflow.config` in the project directory.\n" "2. Declare the configuration options by using the `params` keyword followed by variable names and their default values. For example:\n\n" "```\n" "params {\n" " inputDir = './input'\n" " outputDir = './output'\n" " numThreads = 4\n" "}\n" "```\n\n" "3. You can also override the default values in the configuration file by specifying new values when running the pipeline. For example:\n\n" "```\n" "nextflow run my_pipeline.nf --inputDir /path/to/input --outputDir /path/to/output --numThreads 8\n" "```\n\n" "4. Save the file and use it in your pipeline by calling the parameter name with the `$` symbol. For example:\n\n" "```\n" "process myProcess {\n" " input:\n" " file fastq from \"$inputDir/*_R{1,2}.fastq.gz\"\n" " output:\n" " file(\"${outputDir}/${sampleName}_mapped.bam\")\n" " script:\n" " \"\"\"\n" " my_command --input $fastq --threads $numThreads --output ${outputDir}/${sampleName}_mapped.bam\n" " \"\"\"\n" "}\n" "```\n\n" "Next request.") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html