Too many tutorials simply teach you how to program, without ever teaching you how to make good programs.
Here are some things should consider when choosing variable names.
The variable name should convey what kind of information is contained in the object. Here are some examples:
Good | Bad | |
---|---|---|
age student name count sum product |
a foo xwy |
Don't be afraid of making variable names with more than one word. Just make sure that it's readable.
There are two conventions for doing this:
I prefer the last one, but it's up to you.
Plese do not write 'studentage'. You would not appreciate it if I wrote this tutorial without any spaces.
You should not stop using irb simply because you can use an editor. I showed you irb first for a reason. When you program, you should keep an irb window open, and go back to it whenever you want to experiment with ideas.
This is what irb was designed for. If you use it wisely, it will make you a much better programmer.
Whenever you have a value that should not change, always make it a constant. This way Ruby will help you catch some possible errors.
Some examples:
Pi = 3.14159265 Electron_mass = 9.109e-31 Speed_of_light = 3e8 Earth_Sun_distance = 5.79e10
In general, do not write numerical values directly. Use constants to make your code more clear.
For instance, the formula for the area of a circle is A=πr2. Where r is the radius. Your code should resemble this formula as much as possible.
Good | Bad |
---|---|
PI = 3.14159265 area = PI*radius**2 |
area = 3.1416*radius**2 |