9.5: Summary

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In this chapter an array was defined as a multivalued variable stored in a contiguous area of memory that contains elements that are all the same size. The chapter then showed why each point in this definition is important, and how this definition can be used to implement an array and access array elements. The implementation and access to the array was shown in a number of programs, such as printing the array and sorting the array.

In terms of why this understanding of the true nature of an array is important, most HLL implement extensions to the basic array type, and a programmer who does not understand these extensions in the language is likely to have situations arise where bugs are encountered that are poorly understood. Even concepts as simple as Object arrays in Java are strange because the initial value of all elements is set to null. This is often confusing to new students until it is realized that in Java the size of an Object is unknown until it is allocated, so the only thing which can be used as the actual element in the Object array is the reference.