If the programmer does not know a method's name at compile time (for example, it might be specified by user input), then the method can be invoked in one of two ways, depending upon whether its signature is known:

• Suppose the signature of the method is known at compile time (even though the method name is not). In that case, when the name of the method becomes available at run time, the somLookupMethod, somFindMethod or somFindMethodOk methods or the somResolveByName procedure can be used to obtain a pointer to the method's procedure using name-lookup method resolution, as described in the preceding topics. That method procedure can then be invoked, passing the method's intended receiver, the Environment pointer (if needed), the context argument (if needed), and the remainder of the method's arguments.

• If the method's signature is unknown until run time, then dispatch-function resolution is indicated, as described in the next topic.