sort() in JavaScript for numbers

sort() in JavaScript converts the sorting items to strings during compare.

That’s why [9, 10].sort() returns [10, 9].

If you need to sort value, you have to extend it with compare lambda:

[10, 0].sort(function(a, b) { return a - b; });

Add/Rename “Home” link in WordPress

Blog posts in Wordpress appear mostly on the main page of the site. That’s why you need a link to it at the navigation bar. But some of the themes doesn’t have such a link. Another one has, but it’s called Home mostly. What if you want to rename it to Blog, for example? The thing is that can’t be fixed by WordPress configuaration. The only you can do is to update the theme source code by yourself.

The problem becomes even bigger if your site is not in English. You apply a good theme and… can’t do anything with “Home” label. Like NewsBelarus can’t.

There aren’t any standart way to fix it currently. Install and apply the theme. Then open the main page of your site with your browser (I’ve used Chromium, but Firefox+Firebug or Opera with debugger work fine too) and open Appearance -> Editor in another tab.

Check the source for the HTML around the menu items. Then check the php files of you theme for the place where it is generated. In the most of themes it’s placed in functions.php or header.php. Use menu and home as a keyword to seek in it.

When you’ve found the place, just update it depending on your case:

1) You have no “Home” link, your menu is generated with wp_list_pages(…) function

Write at the top of it another one <li>…</li> block with link to Home page with properly CSS classes.

2) Your menu is generated with wp_page_menu(…) function and you have no “Home” link, or you have “Home” link, but it isn’t written directly in wp_page_manu using ‘show_home’=>true Add ‘show_home’=>”Replacement_for_Home”. If wp_page_manu gets a string in this param, it will be put to Home link as a title.

3) The menu is generated with wp_page_menu or wp_nav_menu Seek in php files (it’s placed in functions.php mostly) for code (probably with another function names) that looks like this:

function mybirdsite_page_menu_args( $args ) {
 $args['show_home'] = true;
 return $args;
}
add_filter( 'wp_page_menu_args', 'mybirdsite_page_menu_args' );

Replace

$args['show_home'] = true;

With

$args['show_home'] = "Replacement_for_Home";

If there aren’t such a lines, add them with properly $args["show_home"]. For wp_page_menu remove the custom menu in  Appearance -> Menus It works because this functions call wp_page_menu actually.

4) The “Home” text is hard-coded If you don’t need i18n, just replace it with the text you need. Otherwise replace it in English version, then put into _e(…) and translate in your language file. This hack is primitive, of course, but isn’t obvious.

C#: Checking for null’s with monads

public static TResult With<tinput tresult="">
(this TInput o, Func<tinput tresult=""> evaluator)
where TResult : class
where TInput : class
{
    return (o == null) ? return null : evaluator(o);
}

Usage:

string postCode = this.With(x => person)
 .With(x => x.Address)
 .With(x => x.PostCode);

Python - filesize in bytes with proper prefix

 
def get_bytes_size_units(num):
  """ Get file size with proper units of measurement.
  """
  range_titles = ["b", "kB", "Mb", "Gb", "Tb", "PB", "EB", "ZP", "YB"]
  range_titles_len = len(range_titles)
  i = 1
  prev_value = 0
  new_value = num
  is_iteration = True
  while is_iteration:
    prev_value = new_value
    new_value = num >> ((i << 1) * 5)
    i += 1
    is_iteration = new_value < 0 and i < range_titles_len
  i -= 2
  return "%.2f%s" % (float(num) / float(1 << ((i << 1) * 5)), range_titles[i])

Incorrect characters in the list of audio devices in Java

Everyone knows, that audio devices are listed in Java with AudioSystem.getMixerInfo(). Mac users know, that the only sound device they have for Macintosh is Built-in Input, Built-In output and Java Sound Audio Engine, version 1.0. And only the ones who use non-latin symbols in OS, know about the problem with this function: Cyrillic letters looks like a habracadabra with it. I’m not sure about Japanese ones, has to be checked still..

Like this:

It happens because getMixerInfo() returns device data in Windows-1252 charset, but tries to output it in Windows-1251. We have to help it somehow

It might be cool to write a wrapper for javax.sound.sampled.Mixer.Info, but toString() and getName() methods in this class are final. Let’s use helper functions:

public class Shared {
 private static String OS = null;
 public static String getOsName()
 {
  if(OS == null)
   OS = System.getProperty("os.name");
     return OS;
 }
 public static boolean isWindows()
 {
    return getOsName().startsWith("Windows");
 }
 public static String toLocalString(Object info)
 {
  if(!isWindows())
   return info.toString();
  String defaultEncoding = Charset.defaultCharset().toString();
  try
  {
   return new String(info.toString().getBytes("windows-1252"), defaultEncoding);
  }
  catch(UnsupportedEncodingException ex)
  {
   return info.toString();
  }
 }
}

Then we use Shared.toLocalString(item.getName()) for every such an instance. All of the titles are ok now:

grep support for \d

A long time ago, when every PC had own OS, it was easy to remember, which RegEx are from POSIX standart, and which appeared only in Perl-style. Now it’s almost forgotten, and C# regexp classes don’t support POSIX character classes (like [:digit:]).

That’s why the debugging of a simple bash script is so difficult. grep is older then a lot of his users, he remembers all of these times and needs -P for Perl mode and ‘\d’ for digits support.

That’s how

ls | grep -e "[0-9][0-9].[0-9][0-9].md"

becames:

ls | grep -Pe "\d{2}.\d{2}.md"

Free and open-source software licenses

There’re plenty of free and open-source software licenses and not all of them are as simple as Do What the Fuck You Want to Public License. And even if you collected all 4 freedoms and 650 pokemons, it isn’t enough.

The main thing a developer has to know about free and open-source licenses – some of them let the code be linked from code in another language, and some of them don’t.

For example, if you use something licensed as GNU GPL. your project has to be under GNU GPL too. In other hand, if you use BSD license, you can sell it to Apple to make OS X from it.

Please, check the license before using something from GitHub or Google Code.

Google Code allows only OSI-Approved licenses. You have to remember this table to be safe using projects from it:

License	Link with code using a different license	Release changes under another license
Apache License	+	+
Artistic License	+	!
Eclipse Public	+	-
GNU GPL 3	-	-
GNU GPL 2	-	-
GNU Lesser	+	-
Mozilla Public	+	!
New BSD	+	+
Microsoft Public License*	+	-

+ – allowed
- – not allowed
! – limited
* Microsoft Public License isn’t included in official list on Google Code, but is approved by OSI too and is very popular on Codeplex.