498. Positive and negative covenants.

As some of the tenant's covenants (such as the covenant to repair) are positive, and others (such as the covenant not to assign) are negative, it is usual to make the proviso for re-entry take effect on the non-performance or non-observance of the tenant's covenants. While these words are appropriate to the positive and negative covenants respectively, a reference to non-performance only will nevertheless apply to a breach of a negative covenant