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---
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id: 5e302e8ce003129199103c79
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title: Part 22
challengeType: 0
2021-01-13 03:31:00 +01:00
dashedName: part-22
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---
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# --description--
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Now let's simplify the `reduce()` callback function by refactoring it.
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Essentially, the current callback function is `(accumulator, currentValue) => { return accumulator + currentValue }` . Since there's only one expression in the function body, we can omit the `{}` . Additionally, we can omit the `return` keyword since that is implicit when using arrow function syntax.
So the function can be simplified to just `(accumulator, currentValue) => accumulator + currentValue` .
Replace the current callback function argument in the `reduce()` function with the simplified callback function from above.
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# --hints--
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See description above for instructions.
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```js
assert(
code
.replace(/\s/g, '')
.match(
/reduce\(\(accumulator\,currentValue\)\=\>accumulator\+currentValue\,0\)/
)
);
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```
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# --seed--
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## --before-user-code--
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```html
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" / >
< title > < / title >
< meta name = "description" content = "" / >
< meta name = "viewport" content = "width=device-width, initial-scale=1" / >
< link rel = "stylesheet" href = "styles.css" / >
< / head >
< body >
< div class = "container" >
< form id = "calorie-form" >
< h2 class = "center" > Calorie Counter< / h2 >
< div class = "grid" >
< legend > Sex< / legend >
< div >
< input type = "radio" name = "sex" id = "female" value = "F" checked / >
< label for = "female" >
Female (2,000 calories)
< / label >
< div >
< input type = "radio" name = "sex" id = "male" value = "M" / >
< label for = "male" >
Male (2,500 calories)
< / label >
< / div >
< / div >
< / div >
< div class = "grid" id = "entries" >
Breakfast
< input
type="number"
min="0"
class="cal-control"
id="breakfast"
/>< br / >
Lunch
< input type = "number" min = "0" class = "cal-control" id = "lunch" / > < br / >
Dinner < input type = "number" min = "0" class = "cal-control" id = "dinner" / >
< / div >
< button type = "button" class = "btn-add" id = "add" >
Add Entry
< / button >
< button type = "submit" class = "btn-solid" id = "calculate" >
Calculate
< / button >
< button type = "button" class = "btn-outline" id = "clear" >
Clear
< / button >
< / form >
< div id = "output" > < / div >
< / div >
< / body >
< / html >
```
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## --after-user-code--
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```html
< / body >
< / html >
```
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## --seed-contents--
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```html
< script >
document.getElementById('calorie-form').onsubmit = calculate;
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function calculate(e) {
e.preventDefault();
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const total = Array.from(document.getElementsByClassName('cal-control'))
.map(meal => Number(meal.value))
.reduce((accumulator, currentValue) => {
//console.log({ accumulator });
//console.log({ currentValue });
return accumulator + currentValue;
}, 0);
//console.log({ total });
}
< / script >
```
# --solutions--
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```html
< script >
document.getElementById('calorie-form').onsubmit = calculate;
function calculate(e) {
e.preventDefault();
const total = Array.from(document.getElementsByClassName('cal-control'))
.map(meal => Number(meal.value))
.reduce((accumulator, currentValue) => accumulator + currentValue, 0);
}
< / script >
```
