Divide and Conquer

Described in one phrase, the histogram project is daunting; but divided into numerous small steps, each of which we can take one at a time, the project becomes less fearsome. Let us consider what the steps must be:

• First, write a function to count the words in one definition. This includes the problem of handling symbols as well as words.
• Second, write a function to list the number of words in each function in a file. This function can use the count-words-in-defun function.
• Third, write a function to list the number of words in each function in each of several files. This entails automatically finding the various files, switching to them, and counting the words in the definitions within them.
• Fourth, write a function to convert the list of numbers that we created in step three to a form that will be suitable for printing as a graph.
• Fifth, write a function to print the results as a graph.

This is quite a project! But if we take each step slowly, it will not be difficult.