The Whiteboard

Matt D

12:00 AM

ok. time to implement this stuff

gl man, ill be interested in what you find out

Matt D

12:41 AM

ok, now i understand exception handling policies, its not what in eed

sihg

Hassan

3:08 AM

Hello guys, I'm a web developer, and i code in HTML, CSS, PHP and jQuery.

I want to start off in Software engineering now, and I wondering with what language to start off! Any suggestions?

Jimmy Hoffa

@Hassan Start with Haskell. If you aren't a software engineer when you're done, at least you'll be a heck of a lot weirder.

SOLID (object-oriented design)

In computer programming, SOLID (Single responsibility, Open-closed, Liskov substitution, Interface segregation and Dependency inversion) is a mnemonic acronym introduced by Michael Feathers for the "first five principles" named by Robert C. Martin in the early 2000s that stands for five basic principles of object-oriented programming and design. The principles when applied together intend to make it more likely that a programmer will create a system that is easy to maintain and extend over time. The principles of SOLID are guidelines that can be applied while working on software to remove ...

user15026

@JimmyHoffa Is this a positive attribute?

Jimmy Hoffa

Just memorize that. Completely. Repeat it to yourself 10 times every morning, and you too can learn to program in 10 years.

@AshleyNunn it's a Haskeller attribute

@Hassan what do you mean "Software Engineer" - if you write much PHP and jQuery you program, thus you are what most call a software engineer of sorts, unless you're not using any process controls and just writing code on the back of toilet paper, in which case it's not the language you should focus on, but rather the process control aspects of SE

Which means getting used to source control, and understanding how it works, controlled deployment techniques and approaches, testing methodologies, lots of softer skills. That's generally the distinction between programmer and software engineer.

Or for a weird approach to becomming a software engineer: Read all of c2, front-to-back, on repeat, until you know the entire technical history of the past couple decades

It sounds ludicrous, but I suspect it would work. Though it wouldn't be dissimilar from hitting yourself in the face with a hardcover copy of the SICP until you know LISP

Hassan

3:29 AM

@JimmyHoffa oops i meant software programming

Jimmy Hoffa

@Hassan jQuery and PHP are software programming languages... you know how to do software programming if you know those...

Hassan

@JimmyHoffa PHP is a back-end Web Programming language, and jQuery is a JavaScript based framework

Jimmy Hoffa

You mean you want to do applications development?

Hassan

Yeah.

I started off with Pascal, 2 years back in school.

I don't know much, just the basics in Pascal.

But, now I wa.nt to move up

*want

Jimmy Hoffa

You could take a look at xamaron I think it's called

Hassan

3:35 AM

(I

No, I mean like,

Jimmy Hoffa

Sorry wrong language

Hassan

Yeah.

Jimmy Hoffa

There's a very modern pascal based language out there

Hassan

C, C++, C#, VB,

Jimmy Hoffa

supposed to be great

Hassan

3:35 AM

Java.

tylerl

@Hassan You can start with Haskell. It's give you a wildly different background in comparison to all your peers. And that won't be a bad thing. But nobody will be able to read your code.

Jimmy Hoffa

@tylerl Hey! I resemble that remark!

tylerl

You can start with Java, which will make you no smarter than your peers, but everyone will be able to read your code

@Hassan for reference, this is the language he's talking about:

Hassan

@tylerl please talk in basic english I find your english difficult.

Jimmy Hoffa

Nonsense! Everyone knows Agda is the language no one runs, they just compile it.

Hassan

3:37 AM

Ok,s top.

If I was to say,

I have experience in OOP.

and a bit experience in C#.

and if I ask,

What is good, "Python, C, C++, C# or Java" based on difficulty to learn it.

user15026

@tylerl All I know about Haskell is that there is a book about it with an elephant on it, because one of my old housemates had it, or talked about it, or something.

tylerl

Ranked easiest to hardest: Python, C#, Java, C, C++

Hassan

Oh, so C# is easy?

Do you know C#?

Jimmy Hoffa

@Hassan They're basically the same language. But then that's the Haskell talking. I agree with @tylerl's ordering.

tylerl

Not compared to python

but compared to C++ EVERYTHING is easy

Hassan

3:39 AM

Lol, rlly?

I'll learn C#.

user15026

As someone who is super new to programming, I keep getting told to start with Python, so I am assuming it must be easy.

Hassan

Ok, I'll go for python then

Jimmy Hoffa

@AshleyNunn yep. play with an online repl.

Hassan

It can be used in web as well as Application Development right?

tylerl

@AshleyNunn It was designed to be easy to learn. That point drove the syntax more than anything else.

Jimmy Hoffa

3:40 AM

@AshleyNunn repl.it/languages

@Hassan People don't do much applications development with Python, mostly back-end serverside stuff like web apps and services and such

Hassan

I see.

Does Python require a compiler or something?

tylerl

It's still surprisingly powerful, but it religiously avoids unnecessary punctuation and keywords.

user20683

It sees a fair bit of use in games

Hassan

Or is it like HTML and PHP.

tylerl

@Hassan interpreted

Jimmy Hoffa

3:41 AM

C# for desktop applications is a good go but that's wrong for you... There's a really good language I need to go dig up

Hassan

Oh, it's interpreted like PHP and HTML?

user20683

it's compiled to a virtual machine

Jimmy Hoffa

remobjects.com/elements/oxygene

THIS

Hassan

I dont get it, should I download a software like Visual Studios or something to run Python

tylerl

C# is powerful, but it's heavily tied to Microsoft. Mono is a really impressive framework, but Miguel has his work more than cut out for him keeping up with an army of thousands.

Jimmy Hoffa

3:42 AM

@Hassan if you know some Pascal, go use that language - it does desktop applications and mobile applications development

and it's a very advanced modern featured language just in the Pascal dialect

Hassan

@JimmyHoffa I hate pascal, it has no User Interface.

Jimmy Hoffa

@Hassan that's nice but what I'm talking about above isn't pascal, just the pascal dialect so it'll be easy for you to understand

but it's a full featured UI applications development language

Hassan

And my IT Teacher said, Pascal is just used to train us how to implement algorithms in an actual programming language.

I see, but I wanna go for some language which I can use to do something.

Can you give me a like to

Compiler or something used to code in Python

Actually, I'll just try to learn C#.

I dont get it, should I download a software like Visual Studios or something to run Python

Can someone suggest me a newbie project in C#?

Like I know the syntax and basics.

(WPF)

Jimmy Hoffa

@Hassan Go download visual studio express and create a new C# project and choose WinForms project

You can drag buttons into place etc on the form, double click them to bring up the dialog to enter code that will be executed when they're clicked on, and in the UI view where it shows the form you're building, click on things and view the properties pane looking at all the properties you can set on those controls

That'll get you started creating a program that has a windows form with buttons and things that can do stuff.

Hassan

@JimmyHoffa I have Visual Studios 2013 Ultimate

Jimmy Hoffa

3:51 AM

After that, go to this website and follow the tutorial: learncs.org

@Hassan great, use that

Have fun

Hassan

I am trying to create a calculator

using C#

(I am not a total newbie, i have a little experience)

After I'm done, I'll show you the source

Jimmy Hoffa

Just post it there when it works. When it doesn't work post it to:

Hassan

Ok. :)

How to pass variables to another function in C# O_O

Hassan

4:10 AM

Anyone here good with C#

Matt D

err?

dont ask to ask just ask

Hassan

4:26 AM

This is my code:

    public void Total(int num)
    {
        lblTotal.Content = Convert.ToInt32(lblTotal.Content) + num;
    }
    private void one_Click(object sender, RoutedEventArgs e)
    {
        Total(1);
    }

As soon as I click the btn named 'one' my program crashes.

I want to do this:

When user clicks the button 'one'

Then in the lblTotal, it should display one.

along with the other display

for example, the current reading is: "5+

When user hits "1" it becomes "5+1"

Matt D

do you ever initalise lblTotal ?

and 5+ as a string is not convertable into an integer

tylerl

@Hassan C# tells you why it crashed whenever it crashes. Read the stack trace and the error message.

Matt D

hmm

an action doesnt return anything, which is the one that does

delegate?

Hassan

4:42 AM

No idea what you guys mean, let me initiate lblTotal

It's all set fine, let me see the error message

This is the exception Details: System.FormatException was unhandled
_HResult=-2146233033
_message=Input string was not in a correct format.
HResult=-2146233033
IsTransient=false
Message=Input string was not in a correct format.
Source=mscorlib
StackTrace:
at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
at System.String.System.IConvertible.ToInt32(IFormatProvider provider)

Matt D

i win! go me!

laughs

Hassan

What?

Matt D

think about what your trying to convert into an integer for a second

what is your string

that you are trying to convert

Hassan

It's an object

I am trying to make a calculator

Matt D

yes

you are trying to convert a string, to an integer

Hassan

4:45 AM

lblTotal.Content = Convert.ToInt32(lblTotal.Content) + num;

Matt D

so. what is lblTotal.Content ?

Hassan

It's a label

It shows the total

actually

the screen

Matt D

right. and you're trying to somehow convert that tooo....

Hassan

I am trying to stick 'num' at the end of the lblTotal.Content

Matt D

yes, we know the problem.

we're trying to get you to realise the problem

lblTotal.Content will be, a string.

Hassan

4:47 AM

Ok,

Matt D

you are trying to convert a string, to an integer

what does the string look like?

5+ ?

Hassan

lblTotal.Content = Convert.ToString(lblTotal.Content) + Convert.ToString(num);

No, the content is totally empty

it depends on the user input

Matt D

great

so, what does an empty string mean, when you convert it to an integer?

Hassan

mmm

Infinite?

Matt D

its an interesting question isnt it

Hassan

4:48 AM

I got the 1 button working btw

indeed is

Matt D

its also why you're getting an exception because c# goes. I HAVE NO IDEA!

Hassan

lblTotal.Content = Convert.ToString(lblTotal.Content) + Convert.ToString(num);

Matt D

and then, same question about say "5+"

Hassan

what?

Matt D

what does that mean when you convert it to an integer?

Hassan

4:49 AM

F**** visual studio stopped working

i hate it when that happen

Matt D.

I thought,

To add the integer value of

num at the end of the existing value, I need to convert the existing value to Int, like the error suggested.

Ok, looks like I am doing well, now! :)

Matt D

here's what I want you to do. I want you to think about the "types" of objects you're dealing with. And try and write your code so that when you add things, you add integers to integers.

you can then turn that into a string to display it

Hassan

Oh,

Matt D

and you can add bits of strings to bits of strings

Hassan

I really appreciate your help on improving my logic.

I am mostly into Dynamic PHP, so I don't have this kind of logic xD

PHP is not strict with data types

Matt D

but adding bits of strings to integers and hoping that the bits of strings are valid integers is going to be pretty ugly

even still, trying to turn "I AM A STRING" into a number php will also cause errors

Hassan

4:56 AM

:)

I never defined types in PHP.

Only when there is a requirement of user_input

I just define, need: string or int

with c_type()

Matt D

even if you didnt define types, there will be times when certain things are assumed

Hassan

*ctype()

Yeah,

I got all the numerical buttons done.

Now, need the symbolic buttons done :)

bro

i got a problem with this

mathematical operators now

help me? :(

@MattD

Matt D

hmm?

Hassan

Matt

I am trying to

Matt D

you're trying to turn some random string into an integer again?

Hassan

5:04 AM

Do this:

    private void add_Click(object sender, RoutedEventArgs e)
    {
        Total("+");
    }

Matt D

what does that even mean?

Hassan

It should stick '+' at

Matt D

Total takes an integer as a parameter

Hassan

    public void Total(int num)
    {
        lblTotal.Content = Convert.ToString(lblTotal.Content) + Convert.ToString(num);
    }

Matt D

why are you passing it a string

Hassan

5:05 AM

So, when I try to do that

Matt D

go back to what i said earlier, add integers to integers, append strings to strings

dont add strings to integers, and integers to strings

Hassan

Error 1 The best overloaded method match for 'Calculator.MainWindow.Total(int)' has some invalid arguments c:\users\administrator\documents\visual studio 2013\projects\calculator\calculator\mainwindow.xaml.cs 78 13 Calculator

Error 2 Argument 1: cannot convert from 'string' to 'int' c:\users\administrator\documents\visual studio 2013\projects\calculator\calculator\mainwindow.xaml.cs 78 19 Calculator

78 13 would be this line: Total("+");

Matt D

what does the error tell you?

Hassan

I dont get any error, I get those errors.

The above.

Matt D

what do those errors tell you

Hassan

5:07 AM

I have no idea what it means.

Matt D

then i would start by trying to understand what that means

Hassan

It says, .total() has invalid arguments.

Matt D

ok

so what arguments does toatl accept, it tells you

and what are you trying to pass to this function?

Hassan

Ok, fixed it.

The problem was.

The + which I was trying to pass was string

And the total was supposed to accept int inputs

Matt D

that was one of the problems. yes

Hassan

5:10 AM

So, I changed it to string and now it works fine

Matt D

that is not how to fix it

Hassan

?

Then hw

I'll show you a screenie

of it workin

Matt D

what you are doing. is trying to get a table into your flat. and rather than take the table apart, you've smashed a hole in the doorframe so it fits

Hassan

lol

prntscr.com/2ueqvf

Matt D

ill keep repeating what i've been saying

add integers to integers

Hassan

5:12 AM

I tried converting it to int

Matt D

append strings to strings

Hassan

oh

So you are saying

Have 2 arguements

One for string and one for INt.

Matt D

thats one possible solution

you want to display the total of the operations

that total is, an integer

or a float. or whatever it happens to be

you want to display the operations requested by the user

Hassan

Total() is a function

Matt D

that will contain a mix of numbers, symbols, penguins

Hassan

5:13 AM

It will only contain

numbers

Matt D

5 + 10 ?

the + isnt a number

Hassan

and

+ - * /

Matt D

none of those are numbers

Hassan

Yeah

Numbers and mathematical operators only

so,

I have one question

private void total_Click(object sender, RoutedEventArgs e)
{
int calculate;
int content;
content = Convert.ToInt32(lblTotal);
calculate = content;
lblTotal.Content = calculate;

}

My total doesnt work ;(

Matt D

dont keep application state in the presentation of forms

ie: dont store your application data in controls, like labels

Hassan

5:28 AM

What?

this is not a form, this is a WPF Application. :*

Can you suggest a fix for my above problem?

?

Matt D

makes no difference

dont store your application state in presentation

Hassan

Mmmm

*I see

mm

So how do I do that, suggest me a fix to your suggestion?

Matt D

you have a variable, in your application, which is your total

and instead of converting the button to a string.

you use that

tylerl

@Hassan is lblTotal.Content an Integer, or a String?

And assuming it's a string, are you trying to assign an integer to it? It certainly appears that you are.

Hassan

6:08 AM

What?

i cant understand

lblTotal.Content is a string

It contains the equation to be solved

eg: 5+5

Matt D

there is presentation

and there is data

you present the equation entered by the user as 5 + 5. how you store that in your application is up to you

you present the total of your operations to the user. how you calculate that, should be done using data stored by the application, not data stored in visible controls

Hassan

I have no idea what you mean.

Please explain widely.

In normal language.

Matt D

lets say that im playing CoD on the xbox

the position of my player is not deteremined by looking at the rendered output (or the screen) and asking it where in the world the player is

the game keeps data about where the player is. and when it renders things. it uses this information to generate presentation information

with your calculator. the total number so far, and what the user has entered should be stored in the calculator

they shouldnt be stored in the buttons on the calculator

Hassan

6:46 AM

Recoding it

tylerl

8:25 AM

@MattD Just noticed what "normal language" means. Literally LOLed.

Christoph

11:14 AM

I asked this question

0

Q: How to manage focus for a small set of simple widgets

I'm developing a set of simple widgets for a small (128x128) display. For example I'd like to have a main screen with an overlay menu which I can use to toggle visibilty of main screen elements. Each option would be an icon with a box around it while it is selected. Button (left, up, right, down...

and I'm starting to doubt that this site is even the right one. Does it belong to stack overflow?

Thomas Owens

1:21 PM

The Workplace has graduated, Beer has moderators. This is a good week for Stack Exchange.

2

Oded

1:44 PM

A few more graduations are coming - waiting on designs.

user20683

2:54 PM

@glenh7 cough Scrapy cough

user41796

3:21 PM

@WorldEngineer True enough. I stopped short of saying "LMGTFY". If you look, there's a stealth comment on my answer to the effect of "this is too long for a comment"

user55340

3:34 PM

Whee! Snow day.

user55340

(yea for companies that allow you to work from home)

user55340

3:47 PM

@JimmyHoffa do you think you could give this question a shot at answering?

user41796

@Christoph You will likely get better answers for that question on Programmers than you would on SO. I think you're asking more about the design & concept as opposed to a particular code issue. I would recommend leaving it on Progs.

user41796

Wheee. More SE repz

user41796

2

Q: Connotation of term autodidact

I would like to know if autodidact has a positive, negative, or neutral connotation behind it. These questions asking about usage imply: A neutral connotation: Autodidactic as a Verb What would you call a person who is not a student, but takes interest in exploring academic topics? Self-Lear...

connotation nuance

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