Building Block Programming

Half way through developing a program you often need to insert a little bit extra. Usually the habit of writing at ten line number intervals will allow the new code to be inserted but the neat progression of the line numbers will be spoilt and t he result is somehow a little less professional. Sometimes there is not enough room for the extra code and the use of GO TO is demanded. The machine is sent off to some less crowded section of the list and sent back after the job is done. This solution works but makes the program very difficult to read at a later time when some amendment is needed. Renumbering a portion of the program allows the extra space to be made available and, if done carefully, the join won’t be noticed.