Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8

Function

  • Match
  • Substitution
  • List
  • Unit Tests
"
^[A-Z,a-z]{3}-[A-Z,a-z]{2}\d{2}-[A-Z,a-z]{3}-\d{3}|^[A-Z,a-z]{2}\d{2}-[A-Z,a-z]{3}-\d{3}$
"
m
1st Alternative
^[A-Z,a-z]{3}-[A-Z,a-z]{2}\d{2}-[A-Z,a-z]{3}-\d{3}
^ asserts position at start of a line
Match a single character present in the list below
[A-Z,a-z]
{3} matches the previous token exactly 3 times
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
Match a single character present in the list below
[A-Z,a-z]
{2} matches the previous token exactly 2 times
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
Match a single character present in the list below
[A-Z,a-z]
{3} matches the previous token exactly 3 times
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
{3} matches the previous token exactly 3 times
2nd Alternative
^[A-Z,a-z]{2}\d{2}-[A-Z,a-z]{3}-\d{3}$
^ asserts position at start of a line
Match a single character present in the list below
[A-Z,a-z]
{2} matches the previous token exactly 2 times
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
Match a single character present in the list below
[A-Z,a-z]
{3} matches the previous token exactly 3 times
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
{3} matches the previous token exactly 3 times
$ asserts position at the end of a line
Global pattern flags
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
m

Test String