if (typeof define !== 'function') { var define = require('amdefine')(module); }

define(function() {
  return {
    indexOf : function(arr, item) {
        return arr.indexOf(item)
    },

    sum : function(arr) {
        var total = 0;
        for (var i in arr) {
            if (typeof(arr[i]) == 'number') total += arr[i]
        }
        return total
    },

    remove : function(arr, item) {
        var index = arr.indexOf(item)
        arr.splice(index,1)
        return arr
    },

    append : function(arr, item) {
        arr.push(item)
        return arr
    },

    truncate : function(arr) {
        arr.pop()
        return arr
    },

    concat : function(arr1, arr2) {
        for (var i in arr2) {
            arr1.push(arr2[i])
        }
        return arr1
    },

    insert : function(arr, item, index) {
        arr.splice(index,0,item)
        return arr
    },

    count : function(arr, item) {
        var total = 0;
        for (var i in arr) {
            if (arr[i] === item) total++
        }
        return total
    },

    duplicates : function(arr) {
        var sorted_arr = arr.sort();
        var results = [];
        for (var i = 0; i < arr.length - 1; i++) {
            if (sorted_arr[i + 1] == sorted_arr[i]) results.push(sorted_arr[i])
        }
        return results
    },

    square : function(arr) {
        for (var i in arr) {
            if (typeof(arr[i]) == 'number') arr[i] = arr[i]*arr[i]
        }
        return arr
    },

    findAllOccurrences : function(arr, target) {
        var results = [];
        for (var i in arr) {
            if (arr[i] === target) results.push(i)
        }
        return results
    }
  };
});