19 lines
749 B
Markdown
19 lines
749 B
Markdown
### join
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Is like `Array.join()` but with an additional argument of `end`(is equal to `separator` by default) which is used to separate the second to last and last items in the array. Returns `""` when the array is empty and the first item when the length of array is 1.
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```js
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const join = (arr,separator = ',',end = separator ) => {
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return arr.reduce((acc,val,i) => {
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return i == arr.length - 2 ? acc + val + end : i == arr.length - 1 ? acc + val : acc + val + separator
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},'')
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}
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```
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```js
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join(); // ''
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join(['pen','pineapple','apple','pen'],',','&'); //"pen,pineapple,apple&pen"
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join(['pen','pineapple','apple','pen'],','); //"pen,pineapple,apple,pen"
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join(['pen','pineapple','apple','pen']); //"pen,pineapple,apple,pen"
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```
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