Where a guarantee is expressed to be given in consideration of the creditor doing a specific act, the creditor's performance of that act is a condition of the operation of the guarantee, not merely a promissory obligation. If the creditor fails to perform, the guarantor is not obliged to pay — there is no question of the effect on the guarantor's interests or of election by the guarantor. This is distinct from discharge for breach of a promissory obligation, where the nature of the obligation and the question of election may arise.
The full text is available to signed-in members, including the 5 later cases that cite this judgment.