How to name variables

Question

• What rules do you use to name your variables?
• Where are single letter vars allowed?
• How much info do you put in the name?
• How about for exam

Answer 1

What rules do you use to name your variables?

Typically, as I am a C# developer, I follow the variable naming conventions as specified by the IDesign C# Coding Standard for two reasons

1) I like it, and find it easy to read. 2) It is the default that comes with the Code Style Enforcer AddIn for Visual Studio 2005 / 2008 which I use extensively these days.

Where are single letter vars allows?

There are a few places where I will allow single letter variables. Usually these are simple loop indexers, OR mathematical concepts like X,Y,Z coordinates. Other than that, never! (Everywhere else I have used them, I have typically been bitten by them when rereading the code).

How much info do you put in the name?

Enough to know PRECISELY what the variable is being used for. As Robert Martin says:

The name of a variable, function, or class, should answer all the big questions. It should tell you why it exists, what it does, and how it is used. If a name requires a comment, then the name does not reveal its intent. From Clean Code - A Handbook of Agile Software Craftsmanship