When is a contract not enforceable?

In Von Hatzfeldt-Wildenburg v. Alexander, [1912] 1 Ch. 284, at 288 - 289, Parker J. wrote: It appears to be well settled by the authorities that if the documents or letters relied on as constituting a contract contemplate the execution of a further contract between the parties, it is a question of construction whether the execution of the further contract is a condition or term of the bargain or whether it is a mere expression of a desire of the parties as to the manner in which the transaction already agreed to will in fact go through. In the former case there is no enforceable contract either because the condition is unfulfilled or because the law does not recognize a contract to enter into a contract.