6. A computer program product comprising one or more computer-readable physical storage media having thereon computer-executable instructions that are structured such that, when executed by one or more processors of a computing system, the computing system is caused to perform a method for identifying validation errors in a visual representation of a graphical model, the graphical model comprising one or more objects that include interrelationship, at least some of the objects capable of being visualized on a display, the method comprising: reading a constraint that comprises one or more rules that the graphical model must adhere to in order to comply with the declarative constraint, the one or more rules specifying how the graphical model should function, and the one or more rules specifying properties, parameters, and relationships that objects of the graphical model should adhere to; imposing the constraint on the graphical model; identifying an object in the graphical model that does not conform with one or more rules of the constraint imposed on the graphical model; reading a declarative definition of the graphical model to ascertain a declarative relationship between the non-conforming object of the graphical model and its visual representation that is rendered on a display, the declarative definition including shapes, types, connectors, and decorators; interpreting the declarative relationship between the non-conforming object of the graphical model and its visual representation to formulate underlying code that when executed causes the computing system to provide a visually distinct attribute related to the visual representation on the display; and causing the computing system to execute the underlying code.
6. A computer program product comprising one or more computer-readable physical storage media having thereon computer-executable instructions that are structured such that, when executed by one or more processors of a computing system, the computing system is caused to perform a method for identifying validation errors in a visual representation of a graphical model, the graphical model comprising one or more objects that include interrelationship, at least some of the objects capable of being visualized on a display, the method comprising: reading a constraint that comprises one or more rules that the graphical model must adhere to in order to comply with the declarative constraint, the one or more rules specifying how the graphical model should function, and the one or more rules specifying properties, parameters, and relationships that objects of the graphical model should adhere to; imposing the constraint on the graphical model; identifying an object in the graphical model that does not conform with one or more rules of the constraint imposed on the graphical model; reading a declarative definition of the graphical model to ascertain a declarative relationship between the non-conforming object of the graphical model and its visual representation that is rendered on a display, the declarative definition including shapes, types, connectors, and decorators; interpreting the declarative relationship between the non-conforming object of the graphical model and its visual representation to formulate underlying code that when executed causes the computing system to provide a visually distinct attribute related to the visual representation on the display; and causing the computing system to execute the underlying code. 13. The computer program product in accordance with claim 6 , wherein the one or more computer-readable physical storage media is one of physical memory media and physical storage media.