I am trying to do something like:
String.prototype.print=function(){trace(??????)}
I can't for the life of me figure out a way to get at the string! Yes I know there are other ways to approach this etc. but...
Not sure what the problem is, using this works fine in anonymous functions.
String.prototype.print=function():String{return "printed "+this;}
var o:Object = "foo";
trace(o.print()); // traces: printed foo
I just tricked the compiler to use an object, because "foo".print() causes
Error: Call to a possibly undefined method print through a reference with static type String.
It looks like you are mixing ActionScript 2 into your ActionScript 3 code. As kapep said, using "this" will work in your example. That is, this is perfectly valid code:
String.prototype.print=function(){trace(this)}
Of course, you are missing a semi-colon but that shouldn't matter:
String.prototype.print=function(){trace(this);} //semi-colon after 'trace(this)'
Depending on your development environment, you might be having trouble viewing trace statements, in general. In Flex Builder, for example, trace statements don't show up at all unless you are in Debug mode. Insert another call to trace to verify that you can see trace statements.
As you said, there are many other ways to approach this, such as extending the String class and adding your "Print" function. If you really can't get this to work, then trying an ActionScript 3 (i.e. Object-Oriented) approach might be your best option.
Related
I have just started a new version of my Crysis Wars Server Side Modification called InfinityX. For better management, I have put the functions inside tables as it looks neater and I can group functions together (like Core.PlayerHandle:GetIp(player)), but I have ran into a problem.
The problem is that the specified method to get the players' name, player:GetName() is being seen as an invalid method, when the method actually is completely valid.
I would like to know if using the below structure is causing a problem and if so, how to fix it. This is the first time I've used this structure for functions, but it is already proving easier than the old method I was using.
The Code:
Event =
{
PlayerConnect = function(player)
Msg.All:CenteredConsole("$4Event$8 (Connect)$9: $3"..player:GetName().." on channel "..player.actor:GetChannel());
System.LogAlways(Default.Tag.."Incoming Connect on Channel "..player.actor:GetChannel());
Event:Log("Connect", player);
end;
};
The below code works when I bypass the function and put the code directly where it's needed:
Msg.All:CenteredConsole("$4Event$8 (Connect)$9: $3"..player:GetName().." on channel "..player.actor:GetChannel());
System.LogAlways(Default.Tag.."Incoming Connect on Channel "..player.actor:GetChannel());
The Error:
[Warning] [Lua Error] infinityx/main/core.events.lua:23: attempt to call method 'GetName' (a nil value)
PlayerConnect, (infinityx/main/core.events.lua: 23)
ConnectScript, (infinityx/main/core.main.lua: 52)
OnClientEnteredGame, (scripts/gamerules/instantaction.lua: 511)
(null) (scripts/gamerules/teaminstantaction.lua: 520)
Any clarification would be appreciated.
Thanks :)
Well, as PlayerConnect is inside the table Event, and you are calling with a ":", add self as first arg in the function, like:
PlayerConnect = function(self, player)
Clearly, player in the first block of code is not the same as player in the second block of code. The problem must be that the caller of Event.PlayerConnect is not passing the same value.
To test that your Event.PlayerConnect function works, try this in the same place as your second block of code:
Event.PlayerConnect(player)
That should work as you expect.
So, the problem comes down to how Event.PlayerConnect is called without the second block of code. I'm not familiar with that game engine so I don't know how it is done. Perhaps reviewing the documentation and/or debugging that area would help. If you print(player) or call the equivalent log function in both cases, you should see they are different. If you can't run in a debugger, you can still get a stack trace with print(debug.traceback("Accessing player, who's value is: "..player)). If there is indeed some kind of table-based player object in both cases, you can try comparing their fields to see how they are different. You might need to write a simple dumping function to help with that.
I have code that looks like this:
var variableX:uint = something;
if (variableX > 1)
{
var variableY:uint = foo;
}
else
{
var variableY:uint = bar;
}
When compiled in FlashDevelop, the compiler gives the following warning:
Warning: Duplicate variable definition.
Being a beginner with AS3 and programming I don't like compiler warnings. The compiler is looking at me through squinted eyes and saying "Ok, buddy, I'll let you off this time. But I'm warning you!" and then doesn't tell me what's so wrong about what I'm doing.
What should I be aware of when I do something like this? I mean I could obviously define the variable outside of if and then this wouldn't be a problem, but maybe there's something more to this? Or is the compiler just giving a helpful nudge saying "hey, you might have accidentally created two different variables with the same name" ?
You're correct in your assessment of the warning. It's just letting you know there was already a variable in scope with that name and that you're about to redefine it. This way you don't accidentally overwrite a variable. Although they may not appear to be in the same scope if you check out variable hoisting on this page you'll see what the deal is: http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7f9d.html
An interesting implication of the lack of block-level scope is that
you can read or write to a variable before it is declared, as long as
it is declared before the function ends. This is because of a
technique called hoisting , which means that the compiler moves all
variable declarations to the top of the function. For example, the
following code compiles even though the initial trace() function for
the num variable happens before the num variable is declared:
My personal tendency is to just bring the definition up top myself to avoid having extra warnings that make me miss more important issues. Been out of AS3 for a while but in large projects people let things go and you end up with 100s-1000s of warnings and relevant ones get buried.
I'm having a problem with my code and I don't know what's up, I've searched online and the _Gx method was suggested as the best way over ones like loadstring(x)... although I would be happy with either, can't get either one to work. What I want to do is, in ComputerCraft, send a function name and argument to a turtle, which I'm doing by saving both values to a table and sending across the table, and then on the turtle's program, have a big list of functions, and using a command, call them from the string sent and insert the arg as well. My error is "attempt to call nil", which I don't quite understand why it's saying that... Thanks in Advance!
EDIT
I've edited my code down, as asked, to show that even stripping all else away, this still fails. I could even strip it down even more by taking the variable completely out, and putting the string straight into the _G. This still fails even doing it like that. I've decided to keep it in because that's how I am actually going to be using it later. Calling the function normally works fine. I'm using version Luaj-jse 2.0.3
function foo ()
print ("HI!")
end
print (_VERSION)
I don't know what rednet is, but it seems like you passes name of function to another Lua VM, which doesn't know anything about this function (this function is absent in that VM's globals table).
So, passing function definition as string and executing it by receiver with loadstring is the only solution.
What does a period with a name before a function mean when calling it in Arduino code (C/C++)?
For example, I am using an OLED display library and one function is called like this:
display.setTextSize(1);
I know what this function does, but what does the syntax mean where there is some variable "display" or something before it?
In other words, why is a function called this way versus a normal call with just the function name and input?
"display" is an instance of an object, or a reference to some global/system variable. The "setTextSize" method is a member of that object. The end result means that you are setting the text size of, or on, "display".
This lets you do things more concisely by being able to say display.setTextSize(1), foo.setTextSize(1) and bar.setTextSize(1) without having to specify unique functions for each different item on which you are setting the text size.
Within setTextSize you will probably see "this". "this" in only this one instance means "display". If you used bar.setTextSize(1), "this" would mean "bar" and so on.
I could be incredibly wrong, but I think its got to do with structures. In the arduino environment there's a few different functions that revolve around using serial communication. They have it set up as a library that gets called on whenever you use Serial.something();
The something could be any of the functions that is part of serial, like Serial.read();
EDIT forgot to put a source in. http://arduino.cc/en/Reference/Serial
Apologies if I'm way off, still new at this, and also can't figure out how to just make a comment.
I'm trying to setup a test in JUnit w/ EasyMock and I'm running into a small issue that I can't seem to wrap my head around. I was hoping someone here could help.
Here is a simplified version of the method I'm trying to test:
public void myMethod() {
//(...)
Obj myObj = this.service.getObj(param);
if (myObj.getExtId() != null) {
OtherObj otherObj = new OtherObj();
otherObj.setId(myObj.getExtId());
this.dao.insert(otherObj);
}
//(...)
}
Ok so using EasyMock I've mocked the service.getObj(myObj) call and that works fine.
My problem comes when JUnit hits the dao.insert(otherObj) call. EasyMock throws a *Unexpected Method Call* on it.
I wouldn't mind mocking that dao in my test and using expectLastCall().once(); on it, but that assumes that I have a handle on the "otherObj" that's passed as a parameter at insert time...
Which of course I don't since it's conditionally created within the context of the method being tested.
Anyone has ever had to deal with that and somehow solved it?
Thanks.
You could also use EasyMock.isA(OtherObj.class) for a little more type safety.
If you can't get a reference to the object itself in your test code, you could use EasyMock.anyObject() as the expected argument to yourinsert method. As the name suggests, it will expect the method to be called with.. well, any object :)
It's maybe a little less rigorous than matching the exact argument, but if you're happy with it, give it a spin. Remember to include the cast to OtherObjwhen declaring the expected method call.
The anyObject() matcher works great if you just want to get past this call, but if you actually want to validate the constructed object is what you thought it was going to be, you can use a Capture. It would look something like:
Capture<OtherObj> capturedOtherObj = new Capture<OtherObj>();
mockDao.insert(capture(capturedOtherObj));
replay(mockDao);
objUnderTest.myMethod();
assertThat("captured what you expected", capturedOtherObj.getValue().getId(),
equalTo(expectedId));
Also, PowerMock has the ability to expect an object to be constructed, so you could look into that if you wanted.
Note also that if you use EasyMock.createStrictMock();, the order of the method calls is also important and if you break this rule, it would throw an unexpected method call.