Use codes representative of uses of calls are defined as a part of a network numbering plan, and a route or a destination for a call is selected in full or in part on the basis of the use code dialed by a caller in conjunction with the called number via a call-processing arrangement (200) that uses stored definitions of syntax (320, 350) and grammar (400, 410) of the network numbering plan. The syntax definitions are definitions (312) of individual symbol strings, including the use codes, and include the string's associated virtual nodepoint index (VNI 334) which indicates the string's influence on call route selection, an indicator (339) of whether the VNI is to be combined with a VNI resulting from any preceding strings in the caller-dialed symbol-sequence, an indicator (338) of whether the VNI resulting from this symbol string is to be combined with a VNI of any succeeding symbol strings in the symbol sequence, and an indicator (333) of the string's influence on destination selection that specifies whether, and how, the symbols of the string are to be modified. The dialed symbol sequence is parsed (340) into symbol strings and the definitions of those symbol strings are used to selectively combine (341) their VNIs and modify (342) their symbols to form a resulting VNI and symbol sequence that specifies the route and the destination for the call.