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peakle.js
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peakle.js
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"use strict";
function Peakle(list) {
this.list = list || [];
this.cur = this.list.length > 0 ? 0 : null;
}
Peakle.prototype = {
get length() {
return this.list.length;
},
get current() {
return this.peak(0);
},
prev: function () {
var prev = this.peak(-1);
if (prev === null)
return null;
this.cur -= 1;
return prev;
},
next: function () {
var next = this.peak();
if (next === null)
return null;
this.cur += 1;
return next;
},
peak: function (adv) {
if (adv === undefined)
adv = 1;
if (this.cur === null)
return null;
if (this.cur >= this.length)
return null;
return this.list[this.cur + adv] || null;
},
move: function (i) {
if (i < 0 || i >= this.length)
return null;
this.cur = i;
return this.current;
}
};
exports.Peakle = Peakle;