Improved apparatus for specifying and computing the current length of varying-length data items, together with methods for computing the current length. The apparatus and methods are used in a digital computer system wherein data items are represented by names associated with name table entry items in memory. The name table entry associated with the name represented by the varying-length data item includes a current number of elements item specifier specifying the address of a current number of elements item which specifies the number of elements currently in the represented varying-length data item. The name table entry further includes an element size specifier specifying the size of the elements. A name processor in the processor uses the current number of elements item specifier to obtain the the address of the current number of elements item and and fetches the current number of elements item from memory. The name translator then calculates the current length using the element size and the current number of elements item.