Cpt law notes part-3

Respected Mr.Singhal,

In your notes No.3 you wrote that " In Unilateral Mistake, The contract is neither void nor voidable." Whereas in my knoledge there are two exceptions.  

Unilateral Mistake – Voidable, only if consent is obtained by fraud or misrepresentation.

Exceptions

[I] Mistake as to the person – If ‘A’ intends to enter into a contract with ‘B’, ‘C’ can not enter into the contract.

[II] Mistake as to the nature of the contract – Foster  v/s  Mackinnon  An old person with weak eye sight         

                                                                                          has signed a bill  of exchange, treating it as a guarantee letter........

Respected Mr.Singhal,

In your notes you wrote that " In case of  Mistake of Indian Law, the contract is not voidable", Sir, instead of "VOIDABLE", There should be "VOID". As voidable word is used, if consent is not free, e.g. coercion, undueinfluence, fraud & misrepresentation. Sir, please also tell about Mistake of Foreign Law. In your notes Bilateral Mistake is of two types, But what about "MISTAKE OF LAW". Why it has been left?