From catalog/rfc5646-langtag.abnf rule: language

Definition

language = 2*3ALPHA ["-" extlang] / 4ALPHA / 5*8ALPHA

extlang = 3ALPHA *2("-" 3ALPHA)

Info

Rulename
language
Dependencies
ALPHA, extlang, language
Used Builtins
ALPHA

Alphabet

Translations

Railroad Diagram

language ALPHA ALPHA ALPHA - extlang ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA

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](|-[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](|[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](|-[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](|[A-Za-z](|[A-Za-z]))))))