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/**
* Obliterator ForEach Function
* =============================
*
* Helper function used to easily iterate over mixed values.
*/
var support = require('./support.js');
var ARRAY_BUFFER_SUPPORT = support.ARRAY_BUFFER_SUPPORT;
var SYMBOL_SUPPORT = support.SYMBOL_SUPPORT;
/**
* Function able to iterate over almost any iterable JS value.
*
* @param {any} iterable - Iterable value.
* @param {function} callback - Callback function.
*/
module.exports = function forEach(iterable, callback) {
var iterator, k, i, l, s;
if (!iterable) throw new Error('obliterator/forEach: invalid iterable.');
if (typeof callback !== 'function')
throw new Error('obliterator/forEach: expecting a callback.');
// The target is an array or a string or function arguments
if (
Array.isArray(iterable) ||
(ARRAY_BUFFER_SUPPORT && ArrayBuffer.isView(iterable)) ||
typeof iterable === 'string' ||
iterable.toString() === '[object Arguments]'
) {
for (i = 0, l = iterable.length; i < l; i++) callback(iterable[i], i);
return;
}
// The target has a #.forEach method
if (typeof iterable.forEach === 'function') {
iterable.forEach(callback);
return;
}
// The target is iterable
if (
SYMBOL_SUPPORT &&
Symbol.iterator in iterable &&
typeof iterable.next !== 'function'
) {
iterable = iterable[Symbol.iterator]();
}
// The target is an iterator
if (typeof iterable.next === 'function') {
iterator = iterable;
i = 0;
while (((s = iterator.next()), s.done !== true)) {
callback(s.value, i);
i++;
}
return;
}
// The target is a plain object
for (k in iterable) {
if (iterable.hasOwnProperty(k)) {
callback(iterable[k], k);
}
}
return;
};