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Remove duplicate lines of a text document

Written byPhuoc Nguyen
Created
31 May, 2021
Last updated
13 Oct, 2021
Category
String
JavaScript version
removeDuplicateLines.js
const removeDuplicateLines = (str) => Array.from(new Set(str.split(/\r?\n/))).join('\n');
TypeScript version
removeDuplicateLines.ts
const removeDuplicateLines = (str: string): string => Array.from(new Set(str.split(/\r?\n/))).join('\n');
Examples
examples.js
removeDuplicateLines(`one
three
two
three
one
four`);

/* Output */
/*
one
three
two
four
*/

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