From catalog/rfc5646-langtag.abnf rule: extlang
Definition
extlang = 3ALPHA *2("-" 3ALPHA)
Info
- Rulename
- extlang
- Dependencies
- ALPHA, extlang
- Used Builtins
- ALPHA
Alphabet
-A…Z a…z
Translations
Railroad Diagram
Swift Regular Expression
[A-Za-z][A-Za-z][A-Za-z]|[A-Za-z][A-Za-z][A-Za-z]-[A-Za-z][A-Za-z][A-Za-z](|-[A-Za-z][A-Za-z][A-Za-z])
POSIX Extended Regular Expression
[A-Za-z][A-Za-z][A-Za-z]|[A-Za-z][A-Za-z][A-Za-z]-[A-Za-z][A-Za-z][A-Za-z](|-[A-Za-z][A-Za-z][A-Za-z])