Connected: An Internet Encyclopedia
3.13 Variable-length Array

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3.13 Variable-length Array

3.13 Variable-length Array

Counted arrays provide the ability to encode variable-length arrays of homogeneous elements. The array is encoded as the element count n (an unsigned integer) followed by the encoding of each of the array's elements, starting with element 0 and progressing through element n- 1. The declaration for variable-length arrays follows this form:

         type-name identifier<m>;
      or
         type-name identifier<>;

The constant m specifies the maximum acceptable element count of an array; if m is not specified, as in the second declaration, it is assumed to be (2**32) - 1.

           0  1  2  3
         +--+--+--+--+--+--+--+--+--+--+--+--+...+--+--+--+--+
         |     n     | element 0 | element 1 |...|element n-1|
         +--+--+--+--+--+--+--+--+--+--+--+--+...+--+--+--+--+
         |<-4 bytes->|<--------------n elements------------->|
                                                         COUNTED ARRAY

It is an error to encode a value of n that is greater than the maximum described in the specification.


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Connected: An Internet Encyclopedia
3.13 Variable-length Array