Abstract: A visual development system is described which allows a user to derive forms from other "ancestor" forms, inheriting their components, properties, and code as a starting point for one's own forms. During system operation, the user selects an "Inherit" menu choice for indicating to the system that the form to be created inherits from an existing ancestor form. Ancestor forms can be any forms already contained in an existing project or in an "object repository" provided by the system. Form inheritance allows the user to create a library of standard form templates, either within a single application or across an entire suite of applications. Any changes made to the ancestor form immediately appear in the descendant forms. Further, the use can customize each form type so derived while still retaining the ability to modify the standard form and have those changes reflected in the derived forms.

Abstract: A method and apparatus to reduce conditional statements in normal code flow. A plurality of contiguous memory pages are allocated as either protected or unprotected. A pointer is defined to point to an address such that an operation (write or read) to an address in the unprotected page will occur when the conditional value is within an accepted range. The address is calculated by using a function of the conditional value as an offset to the pointer. When the conditional value enters the non-accepted or error range, the operation to the address of the pointer offset by the function of conditional value will fall within the allocated protected page. This will result in a faulting pointer and invocation of a signal handler which is independent of the normal code and only executed responsive to the conditional value entering an error range.