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| /**
| * Reduce an array to unique values, optionally into a separate array.
| *
| * @module reduce-unique
| * @example
| * > const unique = require('reduce-unique')
| *
| * > const arr = [ 1, 3, 8, 3, 1, 2, 1, 9, 3, 3 ]
| *
| * > arr.reduce(unique)
| * [ 1, 3, 8, 2, 9 ]
| *
| * > arr.reduce(unique, [ 'one', 'two' ])
| * [ 'one', 'two', 1, 3, 8, 2, 9 ]
| *
| * > arr.reduce([ 3 ])
| * 3
| */
| module.exports = reduceUnique
|
| function reduceUnique (prev, curr) {
| if (!Array.isArray(prev)) prev = [ prev ]
| if (prev.indexOf(curr) === -1) prev.push(curr)
| return prev
| }
|
|
