1. A method of performing hybrid expression evaluation while processing a computer-model of a system, comprising: providing a first modeling domain on a first computational device, the first modeling domain being a type of modeling domain that is a statechart modeling domain or a block diagram modeling domain; providing access from the first modeling domain to a second modeling domain, the second modeling domain executing on the first computational device or a second computational device, the second modeling domain being a different type of modeling domain from the first modeling domain and being a statechart modeling domain or a block diagram modeling domain; evaluating a first part of a hybrid expression in a model of a system in the first modeling domain using a first resolution facility, the hybrid expression being a single expression including at least one expression element from the first modeling domain and at least one expression element from the second modeling domain; providing at least a portion of a remainder of the hybrid expression to the second modeling domain, the remainder including the at least one expression element from the second modeling domain; and evaluating, in the second modeling domain, a second part of the hybrid expression from the remainder of the hybrid expression.