CODEWITHSUNDEEP
pythonregex
Sai
Sai

Reputation: 87

regular Expresssion matching the multple Alphanumeric characters separated by '-'

I'm trying to write a regular expression to match a requirement ID which consists of alphanumeric character and then a '-' and this can occur one or multitple times.

The example string would be:

NXOS-ABCD-005-053 – Requirement No. 1
F56156-ISSU-1 - Requirement No 1

I tried the regex below using regex 101 website but could not get the appropriate result that i would require.

([A-Za-z0-9]+\-)*

My understanding of using the above regex is ; it will match all characters A-Za-z0-9 multiple times , followed by a - and this combination can occur one or more times.

But It gives me logs of groups which i dont anticipate. can i get some help to fine tune the regex as I tried to google a lot but bot confused with various usages. Any help towards this will be much appreciated.

Thank you in advance.

Upvotes: 1

Views: 923

Answers (1)

Wiktor Stribiżew
Wiktor Stribiżew

Reputation: 627128

Note ([A-Za-z0-9]+\-)* can match empty strings, as it matches any zero or more occurrences of a sequence of one or more alphanumeric chars followed with a hyphen. Note there is no hyphen after the last alphanumeric part, so this would not match the whole ID even if it worked as you think it would.

I suggest

^[A-Za-z0-9]+(?:-[A-Za-z0-9]+)*

Or, if it is not at the start of string

\b[A-Za-z0-9]+(?:-[A-Za-z0-9]+)*\b

See the regex demo.

Details:

  • ^ - start of string
  • \b - word boundary
  • [A-Za-z0-9]+ - one or more alphanumeric chars
  • (?:-[A-Za-z0-9]+)* - zero or more repetitions of the pattern sequence inside the non-capturing group:
    • - - a hyphen
    • [A-Za-z0-9]+ - one or more alphanumeric chars
  • \b - word boundary

Upvotes: 1

Related Questions