Last time I wrote an article on how one can encapsulate both HTML and CSS in one entity, called WebComponent. This time I want to tell a bit about how to encapsulate JavaScript and HTML.

When I see an article on Habrahabr titled React something, I think Omg, React again?... But React, just as Ember was always a mystery for me.

Until today.


These days, many web developers use different methodologies to make their web page source look structured and clean. But all those methodologies only work well until you use third-party libraries or involve a new person in your project.

Currently I am working on a long arithmetic problem at the university. This problem is much more complicated than I described or than a task I shall be describing now, but here’s the thing: I needed some part of memory to be allocated from within my function. And I needed this to be done in assembly.


Writing code in assembly language in 2015 seems stupid and meaningless. Yet, this subject has a few huge pros:

  1. understanding how computers/compilers/programs work
  2. optimizations while writing a complex or performance-critical applications
  3. fun

Well, in real life, I’ve never met conditions of such performance requirements when I should be writing some parts of application in ASM. Except, maybe, a few ACM ICPC problems.

So, we got two merely huge pros to write in assembly. Thus, if you are not getting fun of writing applications, you may be not interested in this topic.

This article is academical mostly. People who study something like low-level programming at their universities may be interested.

Apr 6, 2015


A few days ago I’ve found my old game, ShootThem! sources. 

Half of hour being trying to run it, and viola!

Placed all the sources with its dependencies on GitHub:

One has no story (in-game, but has one written before the game presentation on a programming competition for students in Dnepropetrovsk). It has (almost) no colors. No code structure or architecture. No animations. 

It is really plain.

Yet, it was and it is a starting point for me =)

Here are some of game screenshots:

Yesterday I tried to run my university project made with Qt and MySQL. But all I got was strange error message, saying QMYSQL driver is not loaded whilst loaded driver list actually included that one.

Searching all over the internet up ‘til 2 AM and recompiling the whole Qt gave no result except time being wasted. Yeah, and 90% of search results were tutorials on how to recompile Qt MySQL plugin under Windows.

Yet in the morning I found solution and it was beautifully simple! I just performed one step from Deploying Qt applications, actually just copied the plugins/ directory to the dir where the application executable lives (build-debug/ or build-release/ for my project; I hate the default build-#{ProjectName}-Desktop_5_4_1-Debug/ paths); included the sqldrivers/ directory there (just copied) and created (a bit tuned although) the qt.conf file. That file just pointed the plugins path to the custom one:


To sum everything up:

  1. create a plugins/ directory in your build directory
  2. copy Qt/5.4/Src/qtbase/plugins/platforms/ there
  3. copy Qt/5.4/gcc_64/plugins/sqldrivers/ there too
  4. create qt.conf file in build directory and fill it as mentioned above

And one more hint before the end: to debug why your Qt plugins fail use this application startup switch: QT_DEBUG_PLUGINS=1 ./app_name - this will display plugins debug information.

Mar 27, 2015

Tiny java code...


This one was super easy so I did a quick comparison of a couple of ways you can do it; the goal is to count all the alphanumeric (a-zA-Z0-9) characters in the text of a Sherlock Holmes book. There’s probably other ways do do it because there’s lots of ways to do literally anything, but the fastest one here is stripping out all non-alphanumeric characters (\W).

Mar 25, 2015

The new hardcore

Trying some new hardcore =3

Just found some interesting way of implementing Decorator design pattern in Python.

As Jason Smith said in his book (Elemental Design Patterns), “design patterns may be implemened in different ways in different programming languages”.

That’s said, design patterns are not some set of classes which will be implemented in a very similar way in different languages - they are just a way of doing something.

Thus, Decorator pattern is a way of wrapping some method’s or class’ behaviour. In Python it may be done with Context Managers:

from contextlib import contextmanager

def tag(name):
    print "<%s>" % name,
    print "</%s>" % name,

with tag("h1"):
    print "moo",


with tag("div"):
    print "foo",

This code will end up wrapping print "foo" and print "moo" methods with printing some HTML tags around ‘em:


That is interesting as it implements Decorator design pattern in a bit hard-coded way, but using language features, not OOP ones.

Compare it to the "standard" OOP implementation in Python:

# -*-coding:utf-8 -*-
class SimpleText(object):
    def __init__(self, text):
        self.text = text

    def content(self):
        return self.text

    def __str__(self):
        return self.content()

class TagDecorator(SimpleText):
    def __init__(self, text, tag):
        super(TagDecorator, self).__init__(text)
        self.tag = tag

    def content(self):
        return '<{0}>{1}</{0}>'.format(self.tag, super(TagDecorator, self).content())

a = SimpleText('moo')
print('SimpleText: %s' % a)

b = TagDecorator('moo', 'h1')
print('TagDecorator (h1): %s' % b)

This one looks a bit… ugly… right? And though Python does not really care of which type are a and b, we may not need all this class hierarchy.

This is the might of context managers!

Have you ever thought on how this:

could be turned to this:

without manually setting per-pixel sizes?

It’s simple as 1-2! Just take a look at the top of the UI editor and you’ll find a set of buttons, dedicated to do this adjustment for you:

Yet, there is just one small tip: first you should select a containing widget, whose children will be rearranged.

Like this:

Note the selected parent widget for vertical_layout.