Channel 9 - Discussions by amotif

Tech Off - C# array constructor & initialization

amotif — Thu, 29 Nov 2007 00:42:18 GMT

janzenr wrote:

I am under the impression that:

new String[] { "foo", "bar"};

and

new String();

are just constructors. new String(); does not new up to anything, unlike the behavior of the array, right?

    new String[] { "foo", "bar"};

allocates and array and assigns elements

    new String();

would allocate a String instance, if it actually compiled. It won't compile because there is no default ctor for String (String is immutable, so it wouldn't make much sense).

    new Object();

This compiles and creates a new instance of Object. Your "does not new up to anything" statement isn't correct, as far as I understand your words.

janzenr wrote:

Also if I pass new String[] { "Foo", "bar"} as a function's parameter, it compiles. Ex:

Console.WriteLine(new String[] { "foo", "bar" });

We still have a problem here.

I don't see the problem. Your example of passing the initialized array as a parameter is a completely different context than your original question, which tries to use the initialized array as a statement unto itself. And *that* is the subject of the error message you get.

As to "why," I'd guess that has something to do with the language spec.

Tech Off - What's the functional programming / Linq form of this?

amotif — Tue, 27 Nov 2007 01:56:31 GMT

amotif wrote:

Anyone know how to format this to "5=>a,e" etc. in a linq-esque fashion?

Okay, I think I've settled on this:

    var result = from pair in data
                 group pair by pair.Value into g
                 select g.FormatReverseMapping();

    foreach (string s in result)
        Console.WriteLine(s);

with an extension method:

    internal static string FormatReverseMapping(this IGrouping> grouping)
    {
        StringBuilder buffer = new StringBuilder();

        buffer.Append(grouping.Key);
        buffer.Append("=>");
        foreach (var x in grouping)
            buffer.Append(x.Key);

        return buffer.ToString();
    }

(psst-- take a look at Systems.Collections.Generic.KeyValuePair.)

Tech Off - What's the functional programming / Linq form of this?

amotif — Tue, 27 Nov 2007 01:41:37 GMT

Here's an alternative for deriving invert:

    var invert = from pair in data
                 group pair by pair.Value;

Anyone know how to format this to "5=>a,e" etc. in a linq-esque fashion?

Coffeehouse - Trick or Treat?

amotif — Wed, 31 Oct 2007 23:42:08 GMT

W3bbo wrote:

Cute... but JPEG compression is your friend. Those images shouldn't be 600KB big.

And... Jamie rebuts with a 1.2 MB image.

Laser eyes dog is in ur bag
stealin' ur treatz

Coffeehouse - Guys (Jamie?) where's the Channel9's Halloween decoration?

amotif — Wed, 31 Oct 2007 00:44:16 GMT

jamie wrote:

+1. [6]

Coffeehouse - Hi, I'm Chris and I am a VB.NET developer !

amotif — Wed, 24 Oct 2007 23:15:19 GMT

W3bbo wrote:

Maybe it's because you've gotta be pretty incompetant to be a VB.NET developer and not to be able to comprehend a C# example. A VB developer should know the few syntactical differences between C# and VB, because otherwise the languages share an identical paradigm.

Is there a similar correlation for incompetent spellers?

Tech Off - Date loop backwards

amotif — Fri, 19 Oct 2007 21:15:44 GMT

ScanIAm wrote:

If the compiler can figure out that I've got code that won't ever execute or notice that I'm comparing an int to a null, it should be able to find these conditions.

The compiler doesn't know that in this case. All it knows is that you're ignoring the return value, which is a common idiom in code.

Tech Off - Date loop backwards

amotif — Thu, 18 Oct 2007 21:56:15 GMT

DateTime is immutable. Instead of

myDate.AddDays(-1)

try

myDate = myDate.AddDays(-1)

Coffeehouse - Employment.End(me);

amotif — Thu, 18 Oct 2007 15:23:11 GMT

I was laid off once. It was probably the best thing that could have happened to me at the time. I hope it turns out the same for you.

Do you need to stay until Dec. 14th to get the 4 months of severance? Just something to consider. If you do stay, make yourself uber-useful and get a feel for whether they might be able to bring you back in on contract at a cushy rate.

Coffeehouse - Cool It

amotif — Tue, 16 Oct 2007 15:17:42 GMT

Minh wrote:

What's the worse that can happen?

As usual, reasonable people have reasonable answers.

See this video on MSN Soapbox

The action in the left column is the same for both rows, so the economic consequence should be roughly the same. Therefore, the lower left cell should also list global depression.

If you accept that then there is only one cell that doesn't bring economic disaster. And potentially political suicide--you have to convince yourself that climate change is not coming in order to take the easy path, politically speaking.

Coffeehouse - Hi Ho Hi Ho its off to court I go

amotif — Mon, 08 Oct 2007 18:22:46 GMT

rjdohnert wrote:

Me: "Dont get too friendly"
Me: " Is that a trick question?"
Me: "I dont think so"
Me: "Got a warrant?"
Me: "Does this mean I can move without getting a cap in my (I need to watch my language)?"
Me: "Yeah I would have made it to the full 2 years if you hadnt stopped me"
Me: Full smart a$$ mode " Well I was going to Fayetteville street before all the hot looking hookers moved on. Nothing worse then getting there and all the hookers are missing teeth and are riddled with all types of STD's"
Me: " Oh goody. I need the vacation"
Me: " Classified"
Me: "Its whatever"
Me: "sure"

Sounds like you made the situation more difficult than it needed to be.

Coffeehouse - Back to the Futurizer .. Why not Scoble?

amotif — Wed, 03 Oct 2007 21:44:24 GMT

jamie wrote:

maybe you could get him back?

I predict that Scoble will be the guy that replaces the guy that replaced the guy that replaced the guy that replaced the guy that replaced Scoble.

(Using "guy" in the gender-neutral sense, of course.)

Coffeehouse - Windows Vista Line

amotif — Wed, 19 Sep 2007 21:40:55 GMT

DCMonkey wrote:

ZippyV wrote:
I don't get it.

Arrr. Me thinks it's a play on the maps o the London Underground.

Yarr, that's some lovely illustratin', but it won't help ye find the back o' yer britches with both hands, now will it?

Coffeehouse - Arrr! (You know what day it is)

amotif — Wed, 19 Sep 2007 14:07:05 GMT

Avast ye scurvy wag, I know it to be... Wednesday!

Load the starboard guns with grapeshot and show that troll barque a broadside they won't forget! Yarr!!

Coffeehouse - I is a certificate professhunal

amotif — Thu, 06 Sep 2007 13:11:45 GMT

littleguru wrote:

I still has a melon - still ROTFL!

Certificats iz good... nom nom nom nom

Coffeehouse - Tell us about what you do for a living

amotif — Sat, 01 Sep 2007 01:16:28 GMT

Charles wrote:

Come on, Niners. Only 57 responses? Where is everybody? Thank you very much to all who have responded!

Sorry, I tend to ignore the pinned topics. Some of them have been rather long-lived.

Coffeehouse - Long Weekend!

amotif — Sat, 01 Sep 2007 00:52:46 GMT

jamie wrote:

Burrrp

* is there only a long weekend in toronto?

We have one in Seattle, too!

Tech Off - What's behind string.GetHashCode()?

amotif — Fri, 31 Aug 2007 15:19:48 GMT

You shouldn't rely on the implementation details of String.GetHashCode() remaining the same.

Also, GetHashCode isn't guaranteed to return the same value for a given object value from one process to the next, per the docs:

"The GetHashCode method for an object must consistently return the same hash code as long as there is no modification to the object state that determines the return value of the object's Equals method. Note that this is true only for the current execution of an application, and that a different hash code can be returned if the application is run again."

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 18:24:36 GMT

Minh wrote:

Yep! Interviewing people is a head trip. I don't know how Blowdart does it!

I forked a new thread on interviewers: Bad Interviewer, No Cookie

Be gentle.

Coffeehouse - Bad Interviewer, No Cookie

amotif — Wed, 22 Aug 2007 18:23:03 GMT

Thought I'd fork off from the "Interviewing programmers" topic to provide a place for stories of how interviewers go wrong--that's right, you were the one interviewing for a position, and the interviewer, well, you couldn't believe it...

Guidance:

Hard or open-ended questions do not in themselves a bad interview experience make.
Probably best not to reveal the identity or company of the interviewer in question; this is about bad interviewing technique or habits, not humiliation.

For example:

I was interviewing for a C++ position and the C++ "expert" put me through his little C++ quiz. No problem, except that he'd occasionally interject with some clearly false argument to the contrary. I learned as the interview proceded that he used to deal with his know-it-all students that way--by claiming falsehoods to be true. As the interview continued, it occurred to me that some of his "false knowledge" didn't appear to be game playing but what he thought to be fact. Annoying and weird to interview with a true know-it-all (who really doesn't).

(In the following months that I worked with him this behavior continued, often with him spouting something that was easily refuted either from memory or a quick web search. I pretty much gave up on listening to anything he said.)

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 17:53:56 GMT

Minh wrote:

No, he meant obscure question like:

- Why does this statement not give me the right time? DateTime.Now.ToString("hh:MM:ss")

that's design more to show the interviewer's smugness than test the interviewee's ability to work

Hmm, no clue. But I do notice that the minutes, which are incorrect, happen to be the current month... 10:08:21

What really drives me nuts is interviewers who try to show how smart they. Far worse than interviewers who ramble on about the cool stuff they work on when it has nothing to do with what I would be working on.

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 14:41:51 GMT

andy_hanger18 wrote:

Do people really go this nasty and technical in interviews?

By "nasty" do you mean deep probing highly technical questions?

Then, yes, but largely it depends on whether the position is suited for a new grad's knowledge or a seasoned pro's experience.

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 14:37:41 GMT

evildictaitor wrote:

amotif wrote:

Massif wrote:
why "this " + someint.ToString() + " is stupid" is a bad idea

Ooh, good. Are you asking because of the use of ToString() here or because you think there's an inefficinet concat happening--because it's really not. C# 2 will use String.Concat(string,string,string) here. It's probably not any worse than using String.Format.

Even so, String.Format("this {0} is stupid", someint); is preferable because it is shorter, easier to read and easier to localize.

"Easier to read" is rather subjective, but I would suggest that

"this " + someint + " is stupid"

is certainly shorter and easier to read than

String.Format("this {0} is stupid", someint)

Localization is a weenie argument but a valid point if you're hiring someone to write localizable UI code. I've written written localizable UI but haven't met many other people who have. It's certainly a different level of understanding than knowing what the compiler might do with string + string + string.

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 01:47:23 GMT

Riffing on Dispose:

a) Why would you implement IDispose?

b) What's a finalizer?

c) What should you clean up (or not) when Dispose is called?

d) What should you clean up (or not) when the finalizer is called?

e) What's the function that I always forget to call when I implement Dispose? (Interpret as "What's the function you should call when you implement Dispose?")

How many people do you suppose get c) and d) correct?

Coffeehouse - Interviewing programmers

amotif — Wed, 22 Aug 2007 01:43:31 GMT

Massif wrote:

why "this " + someint.ToString() + " is stupid" is a bad idea

Ooh, good. Are you asking because of the use of ToString() here or because you think there's an inefficinet concat happening--because it's really not. C# 2 will use String.Concat(string,string,string) here. It's probably not any worse than using String.Format.