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
No Match

r"
"
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = '{"en": "Male", "es": "Macho"}, {"en": "Female", "es": "Hembra"}, {"en":"Population","es":"Población"}, {"en": "% of total population", "es": "% de la población total"}, {"en": "All cancers", "es": "Todos los cánceres"}, {"en": "All cancers but C44", "es": "Todos los cánceres pero C44"}, {"en": "Number of cases", "es": "Numero de casos"}, {"en": "Age Group", "es": "Grupo de edad"}, {"en": "Year", "es": "Año"}, {"en": "years", "es": "años"}, {"en": "years old", "es": "años"}, {"en": "Age-standardized incidence rate per", "es": "Tasa de incidencia estandarizada por edad por"}, {"en": "Cumulative incidence risk (percent)", "es": "Riesgo de incidencia acumulada (porcentaje)"}, {"en": "cancer sites", "es": "sitios de cáncer"}, {"en": "Time trend analysis need at least 2 years data", "es": "El análisis de tendencia temporal necesita al menos 2 años de datos"}, {"en": "Age at diagnosis", "es": "Edad al diagnóstico"}, {"en": "Estimated annual percentage change", "es": "Cambio porcentual anual estimado"}, {"en": "Regional registries", "es": "Registros regionales"}'; my $regex = qr/{\"en\": {0,1}(\".+), {0,1}\"\w\w\": {0,1}(\".+\")},{0,1}/mp; my $subst = '\\1;\\2'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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 Perl, please visit: http://perldoc.perl.org/perlre.html