; Free NFC v0.1 Reference Grammar
; Status: frozen/stable
; RFC 5234-style ABNF notes. pct-encoded follows RFC 3986.

web-carrier     = "https://" host "/.well-known/freenfc/v1/i/" instance-id *( "/c/" namespace "/" content-id )
native-uri      = "freenfc:v1:i:" instance-id *( ";c=" namespace ":" content-id )

instance-id     = uuid
uuid            = 8HEXDIG "-" 4HEXDIG "-" uuid-version 3HEXDIG "-" uuid-variant 3HEXDIG "-" 12HEXDIG
uuid-version    = %x31-38
uuid-variant    = %x38 / %x39 / %x61 / %x62
namespace       = ALPHA-LOWER / DIGIT *( 0*31( ALPHA-LOWER / DIGIT / "-" ) )
content-id      = 1*2048( unreserved / pct-encoded / sub-delims / ":" / "@" / "/" )
host            = 1*( ALPHA / DIGIT / "-" / "." )
pct-encoded     = "%" HEXDIG HEXDIG
unreserved      = ALPHA / DIGIT / "-" / "." / "_" / "~"
sub-delims      = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="
ALPHA-LOWER     = %x61-7A