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
Processing...

Test String

Code Generator

Language

Generated Code

re = /\b(class|struct)\s+([A-Za-z_]\w*)\s*(:?\s*(public|private|protected)?\s+([A-Za-z_]+))?\s*{(?Us:.*)}\s*;/m str = '.*(class|struct)\\s+([^{]+)\\s*[:]?([^{]+){ \\b(class|struct)\\s+[A-Za-z_]\\s*\\{ #ifndef STUDENTMODEL_H #define STUDENTMODEL_H #include <QAbstractTableModel>v #include <QList> class S : private _jgkdfjgkdlf {}; struct Student { public: int id; QString fio; QString group; QString shifr; double average; }; class StudentModel : public QAbstractTableModel { Q_OBJECT public: explicit StudentModel(QObject* parent = nullptr); Qt::ItemFlags flags(const QModelIndex& index) const override; // basic functionality int rowCount(const QModelIndex& parent = QModelIndex()) const override; int columnCount(const QModelIndex& parent = QModelIndex()) const override; QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const override; QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override; // editable model bool setData(const QModelIndex& index, const QVariant& value, int role = Qt::EditRole) override; bool insertRows(int position, int rows, const QModelIndex& parent = QModelIndex()) override; bool removeRows(int position, int rows, const QModelIndex& parent = QModelIndex()) override; void resetData(const QList<Student>& newData); void readFile(const QString& path); void writeFile(const QString& path); private: QList<Student> _studentData; }; #endif // STUDENTMODEL_H ' # 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