Xah Web Dev Blog Archive 2016-04

Web Design: Navigation Panel Design Problem

JS: Load Order, defer, async, module (rewrote. improved clarity)

Intro to Event-Based Programing (rewrote)

Reddit greed: login popup block content

JavaScript Quiz: Variable in Array

(repost. on its own page)

HTML Frameset is actually really a good UI. Unfortunately, it's killed by geeks for geek reasons.

Today, there's still not a workaround.

see it here: HTML: Frameset to Split Windows

the Java doc is still in html frameset, and it won't be going away anytime soon.

(wow, so this means, browser will actually not deprecate it!)

• JS: Semicolon

(major rewrite, again. Now, explaining the new school of omitting semicolon)

actually, i now tend to think omitting semicolon is better. The rule is just far more simpler. It is also great saver on typing. Also, the semicolon in js is really a pain, because when editing code, refactoring, change between statement and expression, you have to constantly add / remove semicolon. But if you omit them at all times now, you don't have this problem anymore.

Web Design: Relative Date Sucks

the fashionable web design date “posted 834 days ago” is fscking annoying.

it began several years ago… around 2008 maybe.

say no to it.

i think, it'll eventually change back, to real dates.

〔see Web Design Index〕

2 nice JavaScript lib for plotting math functions

function-plot. runs on top of d3js. features interval arithmetics. https://github.com/maurizzzio/function-plot/

jsxgraph. geometer sketchpad like lib. http://jsxgraph.uni-bayreuth.de/wp/index.html • https://github.com/jsxgraph/jsxgraph

• JS: Semicolon

Much update

there are 2 schools of thought. One, the Douglas Crockford classicist, recommend adding semicolon. The other, often younger, JavaScript coding hotshots in industry, recommend ommiting semicolon at all times.

JavaScript SVG set style problem

3 hours spent debugging this

svgElement.setAttribute("style", styleStr)

vs

svgElement.style = styleStr;

The latter does not work on a 2011 old android tablet running 3 years old CyanogenMod running Google Chrome (too lazy to check version).

JavaScript Quiz. Array Splice Insert Without Nesting

// js quiz

// you have
function add () { return ["a","b"]; }
var tt = [1,2,3,4];

// you want
// [ 1, 'a', 'b', 2, 3, 4 ]

// modify tt, using splice. How?

for answer, see Array.prototype.splice

Array.prototype.reduce (new page. Basic example.)

Compute Date Range

Atomic CSS

Array.prototype.flat

see also Array How-To

Array.prototype.every

JS: Test Object Equality 🚀

now, a function that compare 2 arbitrary objects, by deep dive.

Test Array Equality (updated)

DOM: Whitespace Nodes (added more example)

never, use delete to remove element in a array. Use Array.prototype.splice. It is the most general way to insert or remove slices at any position.

See Array.prototype.splice

Function Chaining

new version of JavaScript in Depth is out. Sent to previous buyers.

if you bought it before, please leave a comment or review at Buy JavaScript in Depth. Hopefully positive. Thanks.

Replace All Children, createDocumentFragment

Randomize Node Children 🚀

web bugs is now called web beacon.

that is, those 1 by 1 pixel image file used for tracking. (and many other techniques, now being standardized if not already)

Beacon spec https://www.w3.org/TR/beacon/

json syntax vs JavaScript syntax

JSON syntax isn't just what JavaScript accepts.

JSON

〔see Python: Read Write JSON〕

HTTP Protocol Tutorial (new)

CSS Random Gradient with JavaScript, at CSS: Linear Gradient

CSS: Radial Gradient (minor update)