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'use strict';
// there's 3 implementations written in increasing order of efficiency
// 1 - no Set type is defined
function uniqNoSet(arr) {
var ret = [];
for (var i = 0; i < arr.length; i++) {
if (ret.indexOf(arr[i]) === -1) {
ret.push(arr[i]);
}
}
return ret;
}
// 2 - a simple Set type is defined
function uniqSet(arr) {
var seen = new Set();
return arr.filter(function (el) {
if (!seen.has(el)) {
seen.add(el);
return true;
}
return false;
});
}
// 3 - a standard Set type is defined and it has a forEach method
function uniqSetWithForEach(arr) {
var ret = [];
(new Set(arr)).forEach(function (el) {
ret.push(el);
});
return ret;
}
// V8 currently has a broken implementation
// https://github.com/joyent/node/issues/8449
function doesForEachActuallyWork() {
var ret = false;
(new Set([true])).forEach(function (el) {
ret = el;
});
return ret === true;
}
if ('Set' in global) {
if (typeof Set.prototype.forEach === 'function' && doesForEachActuallyWork()) {
module.exports = uniqSetWithForEach;
} else {
module.exports = uniqSet;
}
} else {
module.exports = uniqNoSet;
}
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