How to use naming-cheatsheet: rules for variable and function names

Get the naming-cheatsheet guide

The guide is a README document, so you can simply read it online on GitHub. If you prefer a local copy, the README gives a clone command for the repository.

Start with the core naming rules

The first sections set the baseline. Use English for names. Pick one naming convention, such as camelCase, PascalCase or snake_case, and keep it consistent across your code. Avoid contractions, so write onItemClick rather than onItmClk.

• Use English when naming variables and functions.
• Pick one naming convention and follow it everywhere.
• Make names Short, Intuitive and Descriptive (S-I-D).
• Do not use contractions.
• Do not repeat the surrounding context in a name, such as handleClick inside a MenuItem class instead of handleMenuItemClick.
• Make the name reflect the expected result, such as isDisabled instead of a negated isEnabled when that reads better in the code.

Name functions with the A/HC/LC pattern

The guide gives this pattern for function names: an optional prefix, then an action (A), then high context (HC), then an optional low context (LC). The order matters because high context carries the main meaning. The README's example is that shouldUpdateComponent means you are about to update a component, while shouldComponentUpdate means the component updates itself.

• getUser: action get, high context User.
• getUserMessages: action get, high context User, low context Messages.
• handleClickOutside: action handle, high context Click, low context Outside.
• shouldDisplayMessage: prefix should, action Display, high context Message.

Choose the right action verb

The guide defines several action verbs. Use get for direct access to data, set to assign a value, and reset to return a value to its initial state. Use remove when taking something out of a collection and delete when erasing something completely. Use compose to create new data from existing data, and handle for callbacks.

• get: accesses data immediately, including async reads.
• set: sets a variable from value A to value B.
• reset: returns a variable to its initial value or state.
• remove: takes something from somewhere, such as removeFilter.
• delete: completely erases something, such as deletePost.
• compose: creates new data from existing data.
• handle: handles an action, often a callback like handleLinkClick.

Use prefixes for booleans and limits

Prefixes make a variable's meaning clearer. The guide uses is for a characteristic or state, has for whether something holds a value, and should for a positive condition tied to an action. It also covers min and max, which the excerpt you have cuts off before explaining.

• is: isBlue, isPresent.
• has: hasProducts is preferred over isProductsExist or areProductsPresent.
• should: shouldUpdateUrl.

Apply the guide during code review

Teams can link the guide in review comments when a name is unclear. Each section pairs a Bad and a Good example, so a reviewer can point to the rule and show the fix. The guide says its ideas apply to any language, though its examples are in JavaScript and it defers to each language's own conventions.

• Quote the section heading that matches the problem.
• Show the Bad and Good example pair from that section.
• Check your language's documentation for official conventions.