varid
convert ident string to hash value, and check conflict
ident prefix sz2 14 bit
ident prefix sz3 21 bit
ident prefix sz4 28 bit
ident prefix sz5 35 bit
ident prefix sz6 42 bit
ident prefix sz7 49 bit
ident prefix sz8 56 bit
ident prefix sz9 63 bit
other 7 bit
use varid::{varid,check,conv};
let map=varid(&["a","e","sz1apple","sz2apple","sz3apple"]).unwrap();
assert!(check("a",map["a"]));
assert!(check("e",map["e"]));
assert!(check("sz2apple",map["sz2apple"]));
assert!(check("sz3apple",map["sz3apple"]));
assert_eq!(conv("a"),36);
assert_eq!(conv("e"),70);
assert_eq!(conv("sz2apple"),12857);
assert_eq!(conv("sz3apple"),1755997);
assert_eq!(conv("sz9apple"),4595417591438920017);