programming-for-dummies

32
Planning Ahead with Structured Programming
Original
Program
Original
Program
Original
Program
Modification #5
Figure 2-1:
Constantly
modifying a
program
eventually
creates an
unorganized
mess.
Modification #1
Modification #2
Modification #1
Modification #3
Modification #2
Modification #4
With constant modifications, a small, simple program can grow into a convoluted
monstrosity that may work, but nobody quite understands how or why.
Because the program consists of so many changes scattered throughout the
code, trying to figure out how the program even works can get harder with
each new modification.
With a simple program, the computer follows each command from start to
finish, so it’s easy to see how the program works. After a program gets modified
multiple times, trying to follow the order of commands the computer follows
can be like untangling spaghetti, hence the term spaghetti programming.
As programs kept getting bigger and more complicated, computer scientists
realized that just letting programmers rush out to write or modify a program
wasn’t going to work any more. So that’s when computer scientists created
the first programming techniques to help programmers write programs
that’d be easy to understand and modify later.
Planning Ahead with Structured Programming
The problem with programs created without any planning is that it
inevitably leads to a mess. So the first step involves keeping a program
organized right from the start.