Apr 262017

If you try converting double.MinValue to string and then back again, you will be greeted with OverflowException:

var text = double.MinValue.ToString(CultureInfo.InvariantCulture);
var number = double.Parse(text, NumberStyles.Float, CultureInfo.InvariantCulture);

Seemingly output string of -1.79769313486232E+308 is a bit lower than double would go despite the implicit promise minimum value makes: to be a minimum.

Reason for this is ToString() method not showing all the digits it can by default but actually a few less with a bit of rounding. This actually generally gives a better result (for example try 1.0/3). Last digit or two are noise anyhow due to the nature of double.

However, if we are emotionally connected to every possible digit or we need to parse stuff we give as output, there is a little thing called round-trip formatting. That works for Single, Double, and BigInteger data types and it consists of a single “r”:

var text = double.MinValue.ToString("r", CultureInfo.InvariantCulture);
var number = double.Parse(text, NumberStyles.Float, CultureInfo.InvariantCulture);

Now we get -1.7976931348623157E+308 as a text representation and parsing fails no more.

PS: Equivalent “issue” exists for .MaxValue.

Apr 212017

If one needs to fill dictionary with bunch of keys while tracking only last value for each, a generic inner loop code might looks something like this:

if (dict.ContainsKey(key)) {
    dict[key] = value;
} else {
    dict.Add(key, value);

Code checks if key exists, if not it is added; otherwise the old value is replaced. Pretty straightforward.

Surprisingly, this code can be simplified – a lot:

dict[key] = value;

Dictionary’s indexed property will do exactly the same thing as code above – but in less lines.

Apr 202017

Nineteen years after the StarCraft’s release, there is yet another patch. Alongside many bug-fixes, it also made StarCraft and Brood War expansion completely free.

While giving the old game for free could be considered a bit of a gimmick in the light of newly announced StarCraft: Remastered, an HD version of the original StarCraft, it is not only that.

Blizzard actually released new features within this patch and that is not the first time. They simply kept up the great customer care of the StarCraft saga. Frankly I wouldn’t be surprised if we see another patch or two for it in the future.

Without the further ado, download the new (free) version and have fun.

PS: And yes, StarCraft color issue has been resolved.

PPS: You can also check some other free games from Blizzard. My personal favorites being The Lost Vikings but also Warcraft II and Diablo are nothing to frown upon. :)

Apr 162017

I already wrote about using Mikrotik’s DNS to resolve a short name lookup in Windows. And there I noted that domain-name DHCP option seemingly has no effect on Linux. Well, let me introduce you to domain search option.

Most of the Linux/Unix based operating systems, whether it is Linux, FreeBSD, or MacOS support arguably a more proper way to define which domain we are referring to when using a single word host name.

To define suffix for domain search, just add option 119:

/ip dhcp-server option
add name="domain-search-option" code=119 value="'example'"

And of course add this option to DHCP network:

/ip dhcp-server network
set 1 dhcp-option=domain-search-option

PS: And no, you cannot use this instead of domain-name. Windows clients only support domain-name while Linux/Mac only supports domain-search option.