Eric Vanderburg coined his laws for programming in
2001. His laws apply to all programming but they are essential to any new
programmer. Professor Vanderburg used the laws in his classes. The
laws are as follows.
1. You allow whatever actions you do not
2. Computers do only what you tell them to
do. Nothing more or less.
3. A program that lacks explicit variable
declaration is destined to error.
Law 1 - "You allow whatever actions you do not
This law is concerned with security. Users of a
program may accidentally or maliciously take actions that will hard the
integrity of an application, its data, or the system on which it resides.
Programmers must be vigilant in restricting the actions users of their software
can take in order to minimize these risks.
Law 2 - "Computers do only what you tell them to
do. Nothing more or less"
Computer programs are simply instructions to the
computer. The computer will read those instructions and execute
them. If an instruction is not given, it should not be assumed to be
executed. This sounds simple but many programmers mistakenly assume
certain actions will be taken. This confusion often happens when things
are computerized. When asked how to take common task and turn that into a
computer program, many people skip steps. People assume
certain things will be completed automatically. For example, take a
guessing number game. A number (X) is chosen out of a pool of available
numbers such as 1-10. The user guesses a number (Y) and then X is compared
to Y. Finally the program would tell the user whether or not they chose
the correct number. This example is very simple but experiments
showed that the step most often skipped was the check of X and Y. In real
life we do not think of the check as a step. It almost naturally happens
but computerization requires that step to be coded in the program.
Law 3 - " A program that lacks explicit variable declaration is
destined to error "
Explicit variable declaration requires a variable used
in a program to be defined with a name and a type. This is used to prevent
errors such as incorrect usage of a variable and incorrect naming. Syntax
varies by programming language but explicit declaration can be turned on with
commands such as “Option Explicit” in Visual Basic.