Composable naming conventions (use prefix) in Vue - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a composable in Vue 3?

A composable is a reusable function that uses Vue's Composition API to share reactive logic across components.

beginner

Why should composables use a prefix in their names?

Using a prefix helps clearly identify composables, avoid name conflicts, and improve code readability by signaling reusable logic.

beginner

Give an example of a good composable name with a prefix.

A good example is useFetchData, where use is the prefix indicating it is a composable function.

beginner

What prefix is commonly used for composables in Vue 3?

The prefix use is commonly used to name composables, like useCounter or useAuth.

intermediate

How does using a prefix for composables help when reading code?

It immediately tells you the function is a composable, so you know it manages reactive state or logic and can be reused across components.

What prefix is recommended for naming Vue composables?

A get

B fetch

C set

D use

The prefix 'use' is the standard for Vue composables to indicate reusable reactive logic.

Why do we use prefixes in composable names?

A To identify composables and avoid name conflicts

B To confuse developers

C To make functions longer

D To make code run faster

Prefixes help identify composables clearly and prevent naming conflicts.

Which of these is a good composable name?

A fetchData

B useFetchData

C dataFetcher

D getData

'useFetchData' uses the 'use' prefix, making it clear it's a composable.

What does a composable usually contain?

A Reusable reactive logic

B Database queries

C CSS styles

D Static HTML templates

Composables contain reusable reactive logic using Vue's Composition API.

If you see a function named 'useAuth', what can you expect?

A It is a Vue component

B It is a CSS class

C It is a Vue composable related to authentication

D It is a database model

'useAuth' follows the composable naming convention and likely manages authentication logic.

Explain why using a prefix like 'use' is important when naming Vue composables.

Think about how naming helps when reading and organizing code.

Describe what a composable is and how naming conventions help in a Vue project.

Focus on the role of composables and the benefit of consistent naming.

Practice

1. Why should composable functions in Vue start with the prefix use?

easy

A. To make them private and inaccessible outside the file

B. To make them run faster in the browser

C. To clearly indicate they are composables and follow Vue conventions

D. To prevent them from being imported accidentally

Solution

1. Step 1: Understand Vue composable naming conventions

   Vue recommends starting composable function names with use to clearly identify them as composables.

2. Step 2: Recognize the purpose of the prefix

   The prefix helps developers quickly know the function is a composable and follows community standards.

3. Final Answer:

   To clearly indicate they are composables and follow Vue conventions -> Option C

4. Quick Check:

   Composable prefix = use [OK]

Hint: Composable names start with 'use' to show their purpose [OK]

Common Mistakes:

• Thinking prefix affects performance
• Believing prefix hides the function
• Ignoring naming conventions

2. Which of the following is the correct syntax for naming a composable that fetches user data?

easy

A. useFetchUserData()

B. fetchUserData()

C. getUserData()

D. userDataFetch()

Solution

1. Step 1: Identify the composable prefix

   The composable should start with use to follow Vue naming conventions.

2. Step 2: Check the full function name

   useFetchUserData clearly shows it is a composable fetching user data.

3. Final Answer:

   useFetchUserData() -> Option A

4. Quick Check:

   Composable name starts with 'use' [OK]

Hint: Composable names always start with 'use' [OK]

Common Mistakes:

• Omitting the 'use' prefix
• Using verbs without 'use'
• Confusing composable with normal functions

3. Given this composable code:

export function useCounter() {
  const count = ref(0);
  function increment() { count.value++ }
  return { count, increment };
}

What will be the output of console.log(counter.count.value) after calling counter.increment() twice?

medium

A. 1

B. 2

C. 0

D. undefined

Solution

1. Step 1: Understand the initial state

   The count ref starts at 0.

2. Step 2: Apply the increment function twice

   Each call to increment() increases count.value by 1, so after two calls, count.value is 2.

3. Final Answer:

   2 -> Option B

4. Quick Check:

   Increment twice = count 2 [OK]

Hint: Increment twice means count.value becomes 2 [OK]

Common Mistakes:

• Forgetting to access .value of ref
• Assuming count resets
• Confusing function call effects

4. Identify the error in this composable naming:

export function fetchData() {
  // composable logic
}

medium

A. Composable functions cannot be exported

B. Function should be a class, not a function

C. Function name is too long

D. Missing 'use' prefix in function name

Solution

1. Step 1: Check naming conventions for composables

   Composable functions must start with use to be recognized as such.

2. Step 2: Identify the missing prefix

   The function fetchData lacks the use prefix, so it breaks the convention.

3. Final Answer:

   Missing 'use' prefix in function name -> Option D

4. Quick Check:

   Composable names need 'use' prefix [OK]

Hint: Composable names must start with 'use' prefix [OK]

Common Mistakes:

• Ignoring naming conventions
• Thinking export is disallowed
• Confusing function types

5. You have multiple composables related to authentication: useAuthLogin, useAuthLogout, and useAuthStatus. Why is using the useAuth prefix a good practice?

hard

A. It groups related composables, making code easier to understand and maintain

B. It makes the composables run faster by grouping them

C. It hides the composables from other parts of the app

D. It automatically imports all composables with the prefix

Solution

1. Step 1: Understand prefix grouping purpose

   Using a common prefix groups related composables logically.

2. Step 2: Recognize benefits of grouping

   This grouping helps developers quickly find and understand related functions, improving maintainability.

3. Final Answer:

   It groups related composables, making code easier to understand and maintain -> Option A

4. Quick Check:

   Prefix groups related composables [OK]

Hint: Use prefixes to group related composables clearly [OK]

Common Mistakes:

• Assuming prefix affects performance
• Thinking prefix hides composables
• Believing prefix auto-imports functions