35 lines
977 B
Markdown
35 lines
977 B
Markdown
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---
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title: Copy an Array with the Spread Operator
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---
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## Copy an Array with the Spread Operator
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- The final hint in the example tells you to use a recently learned method.
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- The spread operator copies all elements into a new empty object.
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```javascript
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while (num >= 1) {
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newArr = [...arr]
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num--;
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}
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```
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- The code above will copy all of the elements into `newArr` but will also reinitialise `newArr` with every new iteration of the while loop.
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- A new variable should first be initialised using the spread operator - `let obj = [...arr];` - then this variable should be added to the `newArr` for every iteration of the while loop.
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## Solution:
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```javascript
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function copyMachine(arr, num) {
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let newArr = [];
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while (num >= 1) {
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// change code below this line
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newArr.push([...arr]);
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// change code above this line
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num--;
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}
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return newArr;
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}
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// change code here to test different cases:
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console.log(copyMachine([true, false, true], 2));
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```
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