JavaScript basics · Lesson 9 of 12 · 7 minutes

JavaScript basics: Named functions

A named function groups a reusable operation; calling it runs its body.

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1
Build named functions
Build this first target: the JavaScript statements shown in the example, as executable-position code rather than a string or comment. Explain how the values and control flow implement this lesson’s concept; this browser lab checks structure without executing arbitrary JavaScript.
Hint & worked example
A named function groups a reusable operation; calling it runs its body.
The requested statements are present as code, not inside a string or comment. No arbitrary JavaScript is executed.
```
function welcome() { return "Welcome to the lab"; }
```
Common mistake to avoid: A string containing code executes automatically when it is assigned.
2
Extend the named functions example
Extend your file to include: the JavaScript statements shown in the example, as executable-position code rather than a string or comment. Explain how the values and control flow implement this lesson’s concept; this browser lab checks structure without executing arbitrary JavaScript.
Hint & worked example
A named function groups a reusable operation; calling it runs its body.
The requested statements are present as code, not inside a string or comment. No arbitrary JavaScript is executed.
```
function welcome() { return "Welcome to the lab"; }
const greeting = welcome();
```
Common mistake to avoid: A successful element lookup guarantees that the rest of an event handler is correct.
3
Verify the complete named functions pattern
Finish the pattern with: the JavaScript statements shown in the example, as executable-position code rather than a string or comment. Explain how the values and control flow implement this lesson’s concept; this browser lab checks structure without executing arbitrary JavaScript.
Hint & worked example
A named function groups a reusable operation; calling it runs its body.
The requested statements are present as code, not inside a string or comment. No arbitrary JavaScript is executed.
```
function welcome() { return "Welcome to the lab"; }
const greeting = welcome();
const heading = greeting + ".";
```
Common mistake to avoid: A string containing code executes automatically when it is assigned.

Understand the pattern

A named function groups a reusable operation; calling it runs its body.

Misconceptions to reject

A string containing code executes automatically when it is assigned.
A successful element lookup guarantees that the rest of an event handler is correct.

This is a code-inspection lab, not a full JavaScript runtime.

Worked example and expected result

function welcome() { return "Welcome to the lab"; }
const greeting = welcome();
const heading = greeting + ".";

A named function groups a reusable operation; calling it runs its body.

Try a variation

Adapt the final example to a different project name while retaining its structure and relationships. A different context still needs a real browser and accessibility check.

Explain it

Which statement correctly explains named functions?A string containing code executes automatically when it is assigned.A successful element lookup guarantees that the rest of an event handler is correct.A named function groups a reusable operation; calling it runs its body.

Apply it elsewhere

You reuse named functions in a different project. What must still be verified?Only whether the source code has the same number of lines.The input values, element availability, and actual behavior in a real browser.Nothing; passing a single exercise guarantees every future use.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

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