How to Name Variables

As software developers we mostly have to follow the rules of logic and the syntax of the languages and frameworks we are using. However, there are a few pieces we do get to decide. We can decide on the names of variables, methods, functions, classes, and id's. Here are some considerations and conventions for how to name them all well.

Domain Specific Language (DSL)

Having a well defined Domain Specific Language (DSL) makes your code easier to read and maintain and it makes it easier to write. A DSL is a specific set of nouns and verbs that let you speak about the functioning of the code in English. For example, in a blog you have should probably name your models Articles and Comments. Your comment could have an attribute author_id which links it to the id of the user who wrote it. @comment.author. This is obvious for a conventional example like a blog. Come up with a more abstract example and how you would name your models, resources, methods, and variables.

Here are some examples of good and bad DSL attribute choices:

Bad

leaving_time
publish_date
price

Good

leaving_at
published_on
price_in_cents

Reserved Words

Although we have a lot of control over "taco" variables, there are a few words that are 'protected' because they are a fixe part of one or many languages.

Javascript	Ruby
`return`	`return`
`true`	`true`
`false`	`false`
`begin`	`begin`
	`def`
	`end`
	`do`
`default`
`this`
`try`

The Dom

	CSS Classes	ID's
Convention	hyphenated	hyphenated
1 Word	'tag'	'name'
2 Words	'tag-list'	'name-input'
Selector	.tag-list	#name-input

JavaScript

Variable	Constructor	function
camelCase	UpperCamelCase	camelCase() (parens)
`firstName`	`Person`	`showForm()`

Ruby/Ruby on Rails

Variable	Model Class	Model Instance	Controller	Table
snake_case	UpperCamelCase	'@'+ snake_case'	UpperCamelCases (plural)	snake_cases (plural)
`current_time`	`User`	`@user`	`UsersController`	`users`