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[cerapa]

That function doesn't return two ints. It returns just one int. (row, col) does not automagically create something that holds two ints, nor does it change the return type of the function.

If you want to return two ints use pair<int, int>, return pair<int, int>(row, col), and pair<int, int> WHATEVER = foo. You can get stuff out of a pair with .first and .second.

[Bumber]

That function doesn't return two ints. It returns just one int. (row, col) does not automagically create something that holds two ints, nor does it change the return type of the function.

If you want to return two ints use pair<int, int>, return pair<int, int>(row, col), and pair<int, int> WHATEVER = foo. You can get stuff out of a pair with .first and .second.

Or use a struct.

[Reelya]

the alternative is to pass by reference or pass by pointer, then modify the sent values. Pass by pointer has one advantage - the calling code needs to put an & before the variable name, which lets you know it's being modified. Normally you should not modify sent parameters.

also Spehss, "const" values cannot be set to a value returned from a function. "const" means "constant" as in "not variable", so they can only be given a value when you declare them.

[Spehss _]

also Spehss, "const" values cannot be set to a value returned from a function. "const" means "constant" as in "not variable".

So I couldn't just do

Code: [Select]

const int foo = bar();
at the start of main()?

I could just make them normal ints then, I only figured I'd use const because it wouldn't be necessary to change them once defined.

[Telgin]

In the new C++ standard I think you can add some kind of type decorator to functions to allow them to do that.  Or... something.  I think the function effectively has to end up as some kind of expression that the compiler can inline at the initialization point of the variable.  The new C++ standard is so different from what I'm used to that it might as well be its own language though, so I'm not sure what the details are.

In general though, no, you can't do that.

[Reelya]

The real advantage of const is that they are set at compile-time rather than runtime. That means that values are hard-wired into your instruction code rather than telling the machine to look up a value somewhere else, as a variable would.

The other main advantage of const is to make function parameters as "const &" - const references.

A reference just tells the function where to find the variable, it just passes the existing variable's memory address, and avoids the default behaviour (pass-by-value) which is to (1) look up the variable, (2) allocate memory for a new variable of the same size (3) call the copy constructor function for the new variable and copy from the old variable, (4) pass the address of the new variavble to your function. So with pass by value, you're calling multiple other functions to pass each parameter to your function. Which is as slow as it sounds.

So, passing by reference whenever possible cuts some overhead down. The danger is that you can then edit a value inside the function and break the calling code unexpectedly. This is where defaulting to "const &" paramters helps. They're passed by reference, but the compile spits and error if you try and change them.

Note that if you pass a const value to a function that also takes const, then it doesn't look up anything, the "hardwired" const value itself is put into the code where you called it, so it is very fast, and explains why you can't pass a non-const variable into a const variable, but you can do the opposite - pass a const value to a non-const parameter - because it copies it into the new variable. Note for "const &" it's the reference that is const, not the variable itself, so you can actually pass non-const values into a "const &" variable.

[Levi]

Woo, I converted my big ancient lab management ruby 1.8.6 rails app into a big exactly-the-same ruby  2.2.2 Sinatra app.

I sure hope nothing explodes.        

[Sappho]

Hello programming friends! I'm writing an article for one of the magazines I work for on programming, and since I'm really not a programmer and have only the most basic understanding of this stuff, I'm hoping one or two of you guys will be willing to answer some questions. I don't want to hijack the thread though - is there anyone who'd be willing to answer a few questions via PM or email (and possibly even have a line or two published in the magazine)?

We may also want to include an interview with a programmer. I think my editor prefers to go with a Czech person, but she may be open to others, if any of you is interested in that. We'd need a text interview (probably by email) and at least one or two good pictures (quality is important - our graphic designers are very picky about having high-quality images). Any volunteers, again, send me a PM.

Thanks guys!

[EnigmaticHat]

I'd love to help but there's no way I'm good enough at programming to be worth interviewing.

[Reelya]

Hello programming friends! I'm writing an article for one of the magazines I work for on programming, and since I'm really not a programmer and have only the most basic understanding of this stuff, I'm hoping one or two of you guys will be willing to answer some questions. I don't want to hijack the thread though - is there anyone who'd be willing to answer a few questions via PM or email (and possibly even have a line or two published in the magazine)?

We may also want to include an interview with a programmer. I think my editor prefers to go with a Czech person, but she may be open to others, if any of you is interested in that. We'd need a text interview (probably by email) and at least one or two good pictures (quality is important - our graphic designers are very picky about having high-quality images). Any volunteers, again, send me a PM.

Thanks guys!

I'm up to answer any questions you have, but I'm not sure about an interview. You are probably best off interviewing someone with more professional credtentials than me I guess.

My credentials are a computer science degree, dabbling in open source and amateur coding projects / homebrew games, some published game programming work for a studio here in Melbourne Australia (on a Game Boy Advance game, this was a while ago) and currently studying a second degree, Bachelor of Games Development. So I can certainly answer most general programming questions, or steer you to where you can get the answers you need.

[Orange Wizard]

Just out of interest (seeing as I am not in any way qualified to be interviewed on the topic), what kind of questions are you wanting to ask?

[Arx]

You are probably best off interviewing someone with more professional credtentials than me I guess.

computer science degree, dabbling in open source and amateur coding projects / homebrew games, some published game programming work and currently studying a second degree, Bachelor of Games Development

Hate to break it to you Reelya, but you've got pretty good professional cred. And good actual cred, having read most of your posts to this thread.

[Sappho]

Looks like we've found 2 possible local candidates for an interview, so that's no longer necessary. This article is very basic. It's for 12-15-year-old Czech learners of English, and they are beginners at the language, so there's no room for real depth. I'm basically just writing an overview of what programming is, things it can be used for, and where the readers can get started learning it. I only have room for maybe 600-700 words total (maybe a bit more if we include a short interview), so there's no room to get too deep into it, unfortunately.

My outline is basically an intro explaining that programming is used to write games, software, web sites, and even things like creating art and doing math. Then there's a section saying anyone can do it - boy, girl, young, old, doesn't matter. Then a little box pointing out that English is important if you want to code, because most programming languages are based on English (and most tutorials and such are in English). Next is a box listing resources for how to get started - again, I'm short on space, so I'm putting code academy, the book "python for kids", and the game "lightbox". I've written all this already. Now I'm working on a short section on what you can do with code, with just a sentence or two on games, applications, web sites, and an example of art made with code (secrettechnology.com).

But it would be cool to include a sentence or two from a few different "real-life" programmers, just to inspire the readers. I'm especially interested in inspiring *female* readers - any female programmers are especially invited to write something about how it's not just for boys, etc. Or a sentence or two about how/why you got started, what your favorite project was... Basically, if you've got the chance to write 1-2 sentences to young potential programmers, what would you want to tell them? I'll work in as many lines from you guys as possible. And when it's done, anyone who helped will get a PDF copy of the article.

EDIT: Oh, holy crap, I just discovered codecombat.com ... This is the COOLEST code-teaching thing I've ever seen. This is going to replace Lightbox in the article, clearly, and also I'm addicted already.

[itisnotlogical]

I thought about maybe creating a script for text-based dialog trees to put on the Unity Asset Store. Maybe $5 at the most; nothing I write is going to compare to the items at the top of the price range, seeing as I can't even wrap my head around writing a custom editor for it.

Anyways, there's a class in the system called dialogOptions, which has a string to put on the UI button, a string referring to the name of the dialogState it links to, and an actual dialogState variable which is filled in at runtime.

For the longest time, it looked like the string was getting nulled somewhere along the line. It wouldn't show up in Debug.Log at any point in execution, and any lines referring to it spat out NullReferenceExceptions. I ran around in circles for hours trying to find the problem, combing up and down Google results and various forums. Near the end, I even considered submitting a bug report for Unity.

It turns out that while I included a string argument in the constructor, at no point in the definition do I ever actually assign a value to the string in dialogOptions. I'm an idiot, I probably should not charge money for anything I write.


EDIT: Also, I commented out some code that removed all listeners before adding new ones, then forgot that I did this. Cue another ten minutes of Googling while I wondered why the number of listeners on the button grew exponentially with every click.

[Bauglir]

Is there any general way to figure out where on a web page an element will appear from the source code, given that the size of the browser window is known in advance? Alternatively, and actually more conveniently, to figure out from an element's position on the page where to look for it in the source code? What I'm trying to do is automate a process that tries to identify and click on certain buttons; I'll be doing some stuff later to try and teach it how to identify what a button is from screenshots of a given website, and which ones are worthwhile, but before I can do that I need to do this.

Since a lot of buttons use images instead of text, and I can't rely on web developers using informative filenames for them, I'm trying to extract information from the appearance of the site as well as its source. It's easy enough to tell a browser to do something to an element of a web page if I know its id or name or something like that, but what I'm using (Selenium) doesn't seem to have an efficient way to do this with coordinates - probably because it's aimed at testing, where you'd have that information and it'd be a lot more reliable, and so I'm sort of abusing the functionality. I just haven't found anything better-suited. Anyway, since I can only interact with the website through a tool that reads its source, I need some way of getting information from some analysis of its appearance into being in terms of its elements.

EDIT: Seems there is. I just needed better Google-Fu. Now I just gotta figure out how to make it work for me.

EDIT: And even basic reading on Selenium shows other ways of doing it. Damn, I suck.