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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

re = /(?<=public:)(.*)(?<=public:)(.*)(?=public:)(.*)/m str = '// Program.cpp #include <iostream>#include <cstdlib>#include <fstream>#include <ctime>using namespace std;enum MALZEME{Ahsap, Aluminyum, Fiberglas, Plastik};class Kisi{private:string isim;int dogumYili;double kilo;public:Kisi(string isim,int dogumYili,double kilo){this->isim = isim;this->dogumYili = dogumYili;this->kilo = kilo;}Kisi(){this->isim = " ";this->dogumYili = 1880;this->kilo = 55;}string getIsim()const{return isim;}int getDogumYili()const{return dogumYili;}double getKilo()const{return kilo;}void YemekYe(double kalori){this->kilo += (kalori/1000); }void Kos(double metre){this->kilo -= (metre/1000);}};class Arac{protected:Kisi surucu;double benzinLitre;public:Arac(string isim,int dogumYili,double kilo,double benzinLitre){this->surucu = new Kisi(isim,dogumYili,kilo);this->benzinLitre = benzinLitre;}Arac(){this->surucu = new Kisi();this->benzinLitre = 60;}void Sur(double km){benzinLitre -= ((km/100)7);surucu->Kos(km/100);}~Arac(){delete surucu;}};class Tekne : public Arac{private:MALZEME malzeme;public:Tekne(Kisi* kaptan,double depo,MALZEME malzeme):Arac(kaptan->getIsim(),kaptan->getDogumYili(),kaptan->getKilo(), depo){this->malzeme = malzeme;}Tekne():Arac(){surucu = new Kisi();benzinLitre = 80;malzeme = Ahsap;}string MalzemeToString(){switch(malzeme){case Ahsap:return "Ahsap";case Aluminyum:return "Aluminyum";case Fiberglas:return "Fiberglas";case Plastik:return "Plastik";default:return "";}}friend ostream& operator<<(ostream& ekran,Tekne& sag){ekran<<"Malzeme: "<<sag.MalzemeToString()<<endl;ekran<<"Depo: "<<sag.benzinLitre<<endl;ekran<<"Kaptan: "<<sag.surucu->getIsim()<<endl;return ekran;}};int main(){Tekne *tekneler = new Tekne[3];tekneler[0] = new Tekne();Kisi *ahmetKaptan = new Kisi("Ahmet",1974,85);Kisi mehmetKaptan = new Kisi("Mehmet",1965,81);tekneler[1] = new Tekne(ahmetKaptan,75,Fiberglas);tekneler[2] = new Tekne(mehmetKaptan,80,Aluminyum);cout<<tekneler[1]<<endl;for(int i=0;i<3;i++) delete tekneler[i];delete [] tekneler;return 0;}' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html