range-set  ::= range ( logical-or range ) *
logical-or ::= ( ' ' ) * '||' ( ' ' ) *
range      ::= hyphen | simple ( ' ' simple ) * | ''
hyphen     ::= partial ' - ' partial
simple     ::= primitive | partial | tilde | caret
primitive  ::= ( '<' | '>' | '>=' | '<=' | '=' ) partial
partial    ::= xr ( '.' xr ( '.' xr qualifier ? )? )?
xr         ::= 'x' | 'X' | '*' | nr
nr         ::= '0' | [1-9] ( [0-9] ) *
tilde      ::= '~' partial
caret      ::= '^' partial
qualifier  ::= ( '-' pre )? ( '+' build )?
pre        ::= prepart ( '.' prepart ) *
prepart    ::= nr | alphanumid
build      ::= buildid ( '.' buildid ) *
alphanumid ::= ( [0-9] ) * [A-Za-z-] [-0-9A-Za-z] *
buildid    ::= [-0-9A-Za-z]+