z-------------

var encodeHTML = function(string) {
    var tempDiv = document.createElement("div");
    tempDiv.innerText = string;
    return tempDiv.innerHTML;
}

/*
encodeHTML("<em>Waffles</em>")
    ==> "&lt;em&gt;Waffles&lt;/em&gt;"
*/

z-------------

// using simpleJSONP.js 
// https://gist.github.com/z-------------/7389e7708a38021cd25e

/* output looks like this (just an example, not actual output)

data: {
    status: 200,
    weather: {
        currentWarnings: [{
            title: "Red Rainstorm Signal",

z-------------

Lucky Duck chords/tabs

by Zachary Guard

    B                 D                 A                 A
D |-----------------|-----4-----4-----|-----------------|-----------------|
A |-----5-----5-----|-5-5---5-5---5-5-|-----4-----7-----|-4-----7-----4---|
E |-7-7---7-7---7-7-|-----------------|-5-5---5-5---5-5-|---5-5---5-5---5-|

    B                 D                 A                 E

z-------------

Array.prototype.search = function(string){
    var matches = [];
    for (i=0; i<this.length; i++) {
        if (this[i].indexOf(string) != -1) {
            matches.push(this[i]);
        }
    }
    return matches;
}

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var header = document.querySelector("header");
var headerHeight = header.offsetHeight;

var oldScroll = 0;

function hideHeader() {
    header.style.top = -headerHeight + "px";
}

function showHeader() {

z-------------

HTMLElement.prototype.center = function(){
    this.style.top = "50%";
    this.style.left = "50%";
    this.style.marginTop = -this.offsetHeight / 2 + "px";
    this.style.marginLeft = -this.offsetWidth / 2 + "px";
}

// document.querySelector("#myDiv").center();
// assumes position absolute or fixed

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var jsonp = function(url,callback) {
    var callbackName = "jsonpCallback"+Math.round(Math.random()*10000000); // make (pretty) sure not to overwrite anything
    window[callbackName] = callback;
    
    var scriptElem = document.createElement("script");
    
    if (url.indexOf("?") != -1) { // url has "?" in it
        scriptElem.src = url + "&callback=" + callbackName;
    } else {
        scriptElem.src = url + "?callback=" + callbackName;

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var xhr = function(url, callback) {
    var req = new XMLHttpRequest();
    req.onload = function() {
        var response = this.responseText;
        callback(response);
    };
    req.open("get", url, true);
    req.send();
};

z-------------

// recursive
var factorial = function(n) {
    if (n == 1) {
        return 1;
    } else {
        return n * factorial(n-1);
    }
}

// iterative

z-------------

var mouse = {};
mouse.coords = {x:-1,y:-1};

window.addEventListener("mousemove",function(e){
  mouse.coords.x = e.clientX;
  mouse.coords.y = e.clientY;
});

/* example:
if (mouse.coords.x > window.innerWidth / 2) {