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

/
/
gms

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?ms)(?P<file_number>\d+)\.\s+(?P<filepath>.*?)\n(?P<file_contents>```(.*?)```)(?=\d+\.\s+|$)" Local $sString = "1. nextflow.config" & @CRLF & _ "```" & @CRLF & _ "params {" & @CRLF & _ " inputDir = "data/raw"" & @CRLF & _ " outputDir = "results"" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "process {" & @CRLF & _ " executor = "local"" & @CRLF & _ " memory = "8 GB"" & @CRLF & _ " cpus = 4" & @CRLF & _ "}" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "2. main.nf" & @CRLF & _ "```" & @CRLF & _ "#!/usr/bin/env nextflow" & @CRLF & _ "" & @CRLF & _ "params.inputDir = "./data/raw"" & @CRLF & _ "params.outputDir = "./results"" & @CRLF & _ "" & @CRLF & _ "include { preprocess, qualityControl, differentialExpression } from "./scripts"" & @CRLF & _ "" & @CRLF & _ "workflow {" & @CRLF & _ " input:" & @CRLF & _ " path(inputDir) from params.inputDir" & @CRLF & _ "" & @CRLF & _ " output:" & @CRLF & _ " path(outputDir) into results" & @CRLF & _ "" & @CRLF & _ " preprocess_output, quality_control_output, differential_expression_output = script {" & @CRLF & _ " preprocess(inputDir)" & @CRLF & _ " } " & @CRLF & _ "" & @CRLF & _ " quality_control_output = script {" & @CRLF & _ " qualityControl(preprocess_output)" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " differential_expression_output = script {" & @CRLF & _ " differentialExpression(preprocess_output)" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "3. scripts/preprocess.sh" & @CRLF & _ "```" & @CRLF & _ "#!/bin/bash" & @CRLF & _ "" & @CRLF & _ "inputDir=$1" & @CRLF & _ "" & @CRLF & _ "# Trim reads using Trimmomatic" & @CRLF & _ "trimmomatic PE ${inputDir}/sample_R1.fastq.gz ${inputDir}/sample_R2.fastq.gz ${inputDir}/sample_R1.trimmed.fastq.gz ${inputDir}/sample_R1.unpaired.fastq.gz ${inputDir}/sample_R2.trimmed.fastq.gz ${inputDir}/sample_R2.unpaired.fastq.gz ILLUMINACLIP:adapters.fa:2:30:10 LEADING:3 TRAILING:3 SLIDINGWINDOW:4:15 MINLEN:36" & @CRLF & _ "" & @CRLF & _ "# Align trimmed reads using HISAT2" & @CRLF & _ "hisat2 -x genome_index -1 ${inputDir}/sample_R1.trimmed.fastq.gz -2 ${inputDir}/sample_R2.trimmed.fastq.gz -S ${inputDir}/sample.sam" & @CRLF & _ "" & @CRLF & _ "# Convert SAM to BAM" & @CRLF & _ "samtools view -bS ${inputDir}/sample.sam > ${inputDir}/sample.bam" & @CRLF & _ "" & @CRLF & _ "# Sort BAM file" & @CRLF & _ "samtools sort ${inputDir}/sample.bam -o ${inputDir}/sample.sorted.bam" & @CRLF & _ "" & @CRLF & _ "# Index sorted BAM file" & @CRLF & _ "samtools index ${inputDir}/sample.sorted.bam" & @CRLF & _ "" & @CRLF & _ "# Remove intermediate files" & @CRLF & _ "rm ${inputDir}/sample.sam ${inputDir}/sample.bam" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "4. scripts/quality_control.sh" & @CRLF & _ "```" & @CRLF & _ "#!/bin/bash" & @CRLF & _ "" & @CRLF & _ "inputDir=$1" & @CRLF & _ "" & @CRLF & _ "# Run FastQC on trimmed reads" & @CRLF & _ "fastqc ${inputDir}/sample_R1.trimmed.fastq.gz ${inputDir}/sample_R2.trimmed.fastq.gz -o ${inputDir}" & @CRLF & _ "" & @CRLF & _ "# Move FastQC output to results directory" & @CRLF & _ "mv ${inputDir}/*.html ${inputDir}/*.zip ${inputDir}/../results/logs" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "5. scripts/differential_expression.sh" & @CRLF & _ "```" & @CRLF & _ "#!/bin/bash" & @CRLF & _ "" & @CRLF & _ "inputDir=$1" & @CRLF & _ "" & @CRLF & _ "# Count reads using featureCounts" & @CRLF & _ "featureCounts -T 4 -a annotation.gtf -o ${inputDir}/counts.txt ${inputDir}/sample.sorted.bam" & @CRLF & _ "" & @CRLF & _ "# Perform differential expression analysis using DESeq2" & @CRLF & _ "Rscript differential_expression.R ${inputDir}/counts.txt ${inputDir}/../results/differential_expression_results.txt" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "Note: The contents of the `data/` and `results/` directories are not provided as they would depend on the specific input data and expected output structure." & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm