mobile.ts

type ConfirmedMobile = string & { __phantom_1548946378096: never }
const createConfirmedMobile = (num: String) => createOf<ConfirmedMobile, String>(num)

type CertifiedMobile = string & { __phantom_1548946391842: never }
const createCertifiedMobile = (num: String) => createOf<CertifiedMobile, String>(num)

const confirmed = createConfirmedMobile('2984829202') 
// ^^^ ConfirmedMobile
const certified = createCertifiedMobile('2984829202') 
// ^^^ CertifiedMobile
const wrongInput = createCertifiedMobile(1234332)
// ^^^ Compilation error: Argument of type '1234332' 
//    is not assignable to parameter of type 'String'.
confirmed == certified 
// ^^^ This condition will always return 'false' 
//   since the types 'ConfirmedMobile' and 
//   'CertifiedMobile' have no overlap.
confirmed === certified 
// ^^^ This condition will always return 'false' 
//   since the types 'ConfirmedMobile' and 
//   'CertifiedMobile' have no overlap.
const anotherCertified: CertifiedMobile = confirmed
// ^^^ compilation error: different types
console.log(typeof confirmed === "string")
// ^^^ true
console.log(typeof confirmed)
// ^^^ "string"
const both = confirmed + '/' + certified
// ^^^ "2984829202/2984829202", because both are type string