Open Mike: Prefixes

> Do You Put Underscores Before Variables?
I only put underscores in front of private variables related to getter/setters, where the “non-underscored” name is already taken, preventing naming conflicts.

Most of my private variables are already obvious why they are private, and therefore don’t need any further clarification. Also, if I decide to change a variable from a private var to a function parameter instead, I would need to remove the underscore from all references. I rarely (if ever) change private variables to public ones, but instead create getter/setters for them, so that type of name change is rarely an issue.

> How About Method Arguments and Interfaces? What Else?
For Interfaces, I use a standard “I” prefix (and I feel like Apple’s naming committee every time I do so)

For parameters, I use no special notation, which maybe isn’t the best, because I have some code where I need to clarify the difference between a public property and the function parameter (most often in the constructor)
public function Car(color:Color, size:int):void //Constructor
{
//”this.color” refers to the getter/setter, while the “color” refers to the function parameter. :(
this.color = color;
this.size = size;
}

As for others, I tend to name all BitmapData variables something like “originalBMD” or “monaLisaBMD” and sometimes use the “BMP” for bitmaps if they are closely tied to the BitmapData.

> Hungarian Notation: Yea or Nay?
Systems Hungarian, no. What if down the line you decide to change the “int” to a “Number” instead? Variable renaming with Find and replace is handy, but can cause some unexpected changes to your code, and should therefore be avoided, not to mention the confusion of changing names mid-code.

Apps Hungarian, yes, on occasion. I don’t adhere to it super strictly, but if it makes the purpose of the variable more clear, then I use it. For instance, I may name an array of instances “instances” or “instances”, but the amount of children in that array “numInstances”. So in that case, naming the “count” variable “instances” instead would be very misleading.

Anyway, that’s my $4 (I think I wrote too much for it to only total 2 cents) of strongly opinionated coding styles. :P

So what about you, Mike? What standards do you use?

“All Hungarian notation is a sin” – I’d take longer variables names ( auto completed ) than a system of random prefix’s. Take the perfect example of using just a d infront of something.

trace(“” + dAngle);

At glance if you were to stumble across this in your class, is the d for distance? could be degrees?. In fact it could be deduction or even defined.

Hell d could even mean destination.

“Do You Put Underscores Before Variables?”

Only when they need a getter / setter, otherwise there is no need to put an underscore before the variable.
If I see an underscore in my code, I know there is a getter / setter for that variable.

Nobody’s perfect, but I try to stick to the Flex SDK coding conventions and best practices document as much as possible:
http://opensource.adobe.com/wiki/display/flexsdk/Coding+Conventions

Scarybug brings up a trend I have noticed where $ as a prefix is used to identify function parameters. I don’t know how I feel about this. On the one hand, I can see how it would help you keep your vars straight, but on the other hand it goes against common custom and that $ really stands out like an eyesore to me when I see it. I’d like to hear some better arguments against it though.

To say the truth, sometimes i use underscore before a private/protected variable… the correct is not to use, and the function parameters are not the same as the private classes…

For example;
package{
public class Main(){
private var testvar:String=”mytestvar”;
public function testfunction(testvar:String):void{
trace(testvar==this.testvar); //if you pass the parameter “mytestvar” it will return true, otherwise false…
}
}
}

var instance=new Main();
instance.testfunction(“mytestvar”); //true
instance.testfunction(“othervar”); //false

So there is no reason for use _ (underscore) before variables, but sometimes i use…