I'm editing an ActionScript file and I've run into an issue.
When I put the following, everything is fine.
if (x=x) {
//blah
}
If I put this, it says unexpected ; for one line and } for the another:
for (x=x) {
//blah
}
Same with when I put this:
while (x=x) {
//blah
}
Of course I only put those there as examples to test it, because I thought something was wrong with my code. Is ActionScript, in this part of my file, only allowing IF statements or what? I need to do the same long series of steps to two different strings, but I don't want to put the code in there twice. Do I have to make a function?
Read up on the looping syntax here.
The For loop doesn't take a boolean (true/false), it needs a counter, a boolean check for the limit and an increment.
i.e.
for (counter; condition; action){
statements;
}
I've never used action script but I would suggest trying this with
x==x
Since once = is assignment, not a comparison.
if the for loop still does not function try
for(;x==x;){
}
the semicolons tell it that you want to only use the second statement in the for loop declaration, the condition; since for loops use three statements,
for (variable; condition; iterative action)
by placing semicolons before and after x==x you specify only the condition, which seems to be what you're trying to do.
Turns out using any IF or WHILE statements caused the error no matter what was inside.
I was able to accomplish what I wanted by making another function and sending each string though those.
Appreciate the help, voted up on both of y'all.
you have to write it like this:
if(a==x){
// do that
}
for (x=0; x<maxloops; x++){
// do that
}
while(a==x){
}
The = symbol is used to define values to varialbes, while == has to be used when you comparing / checking (i.e. whether this is equal to that). This both applies to IF and WHILE
the FOR LOOP. Let's say that you want to execute the action "do that" 10 times. then you write
for (x=0; x<10; x++){
// do that
}
the first part x=0 is the definition of the counting variable and its initial value
the second part is the condition (run the loop as long as x is less than 10)
the third part is the stepper. (how the counter will raise its value in each loop). x++ is a short way to write x = x +1;
Related
I have a Lua function where I build a table of value and attempt to add it to a global table with a named key.
The key name is pulled from the function arguments. Basically, it's a filename, and I'm pairing it up with data about the file.
Unfortunately, the global table always comes back nil. Here's my code: (let me know if you need to see more)
(Commented parts are other attempts, although many attempts have been deleted already)
Animator = Class{}
function Animator:init(atlasfile, stringatlasfriendlyname, totalanimationstates, numberofframesperstate, booleanstatictilesize)
-- Define the Animator's operation mode. Either static tile size or variable.
if booleanstatictilesize ~= false then
self.isTileSizeStatic = true
else
self.isTileSizeStatic = false
end
-- Define the total animation states (walking left, walking right, up down, etc.)
-- And then the total frames per state.
self.numAnimationStates = totalanimationstates or 1
self.numAnimationFrames = numberofframesperstate or 2
-- Assign the actual atlas file and give it a programmer-friendly name.
self.atlasname = stringatlasfriendlyname or removeFileExtension(atlasfile, 'animation')
generateAnimationQuads(atlasfile, self.atlasname, self.numAnimationStates, self.numAnimationFrames)
end
function generateAnimationQuads(atlasfile, atlasfriendlyname, states, frames)
spriteWidthDivider = atlasfile:getWidth() / frames
spriteHeightDivider = atlasfile:getHeight() / states
animationQuadArray = generateQuads(atlasfile, spriteWidthDivider, spriteHeightDivider)
animationSetValues = {atlasarray = animationQuadArray, width = spriteWidthDivider, height = spriteHeightDivider}
--gAnimationSets[#gAnimationSets+1] = atlasfriendlyname
gAnimationSets[atlasfriendlyname] = animationSetValues
--table.insert(gAnimationSets, atlasfriendlyname)
end
Note: when using print(atlasfriendlyname) and print(animationSetValues), neither are empty or nil. They both contain values.
For some reason, the line(s) that assign the key pair to gAnimationSets does not work.
gAnimationSets is defined a single time at the top of the program in main.lua, using
gAnimationSets = {}
Animator class is called during the init() function of a character class called Bug. And the Bug class is initialized in the init() function of StartState, which extends from BaseState, which simply defines dummy init(), enter(), update() etc. functions.
StartState is invoked in main.lua using the StateMachine class, where it is passed into StateMachine as a value of a global table declared in main.lua.
gAnimationSets is declared after the table of states and before invoking the state.
This is using the Love2D engine.
Sorry that I came here for help, I've been picking away at this for hours.
Edit: more testing.
Trying to print the animationQuadArray at the index gTextures['buganimation'] always returns nil. Huh?
Here's gTextures in Main.lua
gTextures = {
['background'] = love.graphics.newImage('graphics/background.png'),
['main'] = love.graphics.newImage('graphics/breakout.png'),
['arrows'] = love.graphics.newImage('graphics/arrows.png'),
['hearts'] = love.graphics.newImage('graphics/hearts.png'),
['particle'] = love.graphics.newImage('graphics/particle.png'),
['buganimation'] = love.graphics.newImage('graphics/buganimation.png')
}
Attempting to return gTextures['buganimation'] returns a file value as normal. It's not empty.
My brain is so fried right now I can't even remember why I came to edit this. I can't remember.
Global table in Main.lua, all other functions can't access it.
print(gTextures['buganimation']) works inside the function in question. So gTextures is absolutely accessible.
Table isn't empty. AnimationSetValues is not empty.
I'm adding second answer because both are correct in context.
I ended up switching IDE's to VS Code and now the original one works.
I was originally using Eclipse LDT with a Love2D interpreter and in that environment, my original answer is correct, but in VS Code, the original is also correct.
So Dimitry was right, they are equivalent, but something about my actual Eclipse setup was not allowing that syntax to work.
I switched to VS Code after I had another strange syntax problem with the interpreter where goto syntax was not recognized and gave a persistent error. The interpreter thought goto was the name of a variable.
So I switched, and now both things are fixed. I guess I just won't use LDT for now.
Solution: Lua syntax. Brain Fry Syndrome
I wrote:
animationSetValues = {atlasarray = animationQuadArray, width = spriteWidthDivider, height = spriteHeightDivider}
Should be:
animationSetValues = {['atlasfile']=atlasfile, ['atlasarray']=animationQuadArray, ['width']=spriteWidthDivider, ['height']=spriteHeightDivider}
Edit: I'm fully aware of how to use answers. This was posted here to reserve my spot for an answer so I could edit it later when I returned back home, which is exactly what I'm doing right now. I'll keep the old post for archival purposes.
Original:
I solved it. I apologize for not posting the solution right now. My brain is melted into gravy.
I will post it tomorrow. Just wanted to "answer" saying no need to help. Solved it.
Solution is basically, "oh it's just one of those Lua things". Wonderful. I'm having so much fun with this language - you can tell by my blank expression.
From the language without line endings or brackets, but forced print parentheses... ugh. I'm going back to C# when this class is done.
Actually I am writting a programming language in Lua. It was quite fun. I've wrote a bit of standard library (stack op and simple io). Then I've thought about labels. It would look like in assembly. While and for loop aren't funny in any bit so programming in that language can be quite challenging. Here are some requirements for this system:
Label stack (or array, dictionary) must be accessible from global context.
Jump instruction handler will be in separate file.
This is how my label-handling function look like:
function handleLabel(name,currentLine)
end
I have no idea how to implement this kind of magic. First I've thought about that:
LabelLineIDS = {}
Labels = {}
Labelamount = 1;
function handleLabel(name,currentLine)
LabelLineIDS[Labelamount]=currentline
Labels[Labelamount]=name
Labelamount=Labelamount+1
end
-- In file "jump.lua":
local function has_value (tab, val)
for index, value in ipairs(tab) do
if value == val then
return index
end
end
print ("Error: Label not defined.") -- Bail out.
os.exit(1)
end
local function _onlabel()
local labelName = globalparams --Globalparams variable contain parameters to each function, at the moment
--this will contain label name. It _can_ be nil.
return LabelLineIDS[has_value(Labels, labelName)]
end
CurrLine = _onlabel() --Currline - current line that get's parsed.
--1 command per one line.
But I'm unsure is this well written or even work. Can you give me idea how to parse labels in my programming language (and write jump functions)? Or if my code is pretty ok at the moment, can you help me to improve it?
Using line counter in my parser I've decided to implement gotos like we can see in BASIC. Thanks everyone for help.
What would be the best way to capture the inner text in the following case?
inner_text = any*;
tag_cdata = '<![CDATA[' inner_text >cdata_start %cdata_end ']]>';
The problem is, it seems like the cdata_end action fires several times due to the fact that inner_text could match ].
I found the solution. You need to handle non-determinism. It wasn't clear initially, but the correct solution is something like this:
inner_text = any*;
tag_cdata = '<![CDATA[' inner_text >text_begin %text_end ']]>' %cdata_end;
action text_begin {
text_begin_at = p;
}
action text_end {
text_end_at = p;
}
action cdata_end {
delegate.cdata(data.byteslice(text_begin_at, text_end_at-text_begin_at))
}
Essentially, you wait until you are sure you parsed a complete CDATA tag before firing the callback, using information you previously captured.
In addition, I found that some forms of non-determinism in Ragel need to be explicitly handled using priorities. While this seems a bit ugly, it is the only solution in some cases.
When dealing with a pattern such as (a+ >a_begin %a_end | b)* you will find that the events are called for every single a encountered, rather than at the longest sub-sequence. This ambiguity, in some cases, can be solved using the longest match kleene star **. What this does is it prefers to match the existing pattern rather than wrapping around.
What was surprising to me, is that this actually modifies the way events are called, too. As an example, this produces a machine which is unable to buffer more than one character at a time when invoking callbacks:
%%{
machine example;
action a_begin {}
action a_end {}
main := ('a'+ >a_begin %a_end | 'b')*;
}%%
Produces:
You'll notice that it calls a_begin and a_end every time.
In contrast, we can make the inner loop and event handling greedy:
%%{
machine example;
action a_begin {}
action a_end {}
main := ('a'+ >a_begin %a_end | 'b')**;
}%%
which produces:
I am having a lot of headache trying to make a game loop in Actionscript. Searched a lot and could not to find the answer. My idea is:
When de game starts, it defined the units sequence of attack, based in their speed (each player can have until 8 units, of any kind). I store this sequence into an Array. I did create the engine in Javascript returning the values in console.log... and works fine... but transporting it to AS3, the things aren't working as I thought.
So... I have the sequence... and now I do the loop
This is my logic (not using any specific language):
for (i = 0; i < sequence.length; i++) {
isHitting = sequence[i]; // first unit from list is the hitter
isDefending = mostPowerfulEnemy(); // method to check who will be attacked
// here is the problem!!!!
isHitting.moveTo(isDefending); // method to move the MC near the target
var kills = isHitting.hit(isDefending); // calc the damage and return the kills
if (isDefending.amount <= 0) {
// remove the MC from Stage and the sequence list
continue; //to move to the next hitter in sequence
} else {
isDefending.amount -= kills;
continue; //to move to the next hitter in sequence
}
}
The problem is: all units are moving at same time!
I've learning about Events and the method addEventListener() sounds like the best option, but i have to call a function, right? I do it... so the unit move to the point... hit... and stop... I need a way to say: "hey, this unit already did his move, did stop and did hit the target, you can now continue the loop" (since I cant return a continue, ofc)
This is what I want:
Some suggestion?
Sorry my bad english.
I'm trying to get a handle on how OOP is done in Lua, and I thought I had a simple way to do it but it isn't working and I'm just not seeing the reason. Here's what I'm trying:
Person = { };
function Person:newPerson(inName)
print(inName);
p = { };
p.myName = inName;
function p:sayHello()
print ("Hello, my name is " .. self.myName);
end
return p;
end
Frank = Person.newPerson("Frank");
Frank:sayHello();
FYI, I'm working with the Corona SDK, although I am assuming that doesn't make a difference (except that's where print() comes from I believe). In any case, the part that's killing me is that inName is nil as reported by print(inName)... therefore, myName is obviously set to nil so calls to sayHello() fail (although they work fine if I hardcode a value for myName, which leads me to think the basic structure I'm trying is sound, but I've got to be missing something simple). It looks, as far as I can tell, like the value of inName is not being set when newPerson() is called, but I can't for the life of me figure out why; I don't see why it's not just like any other function call.
Any help would be appreciated. Thanks!
Remember that this:
function Person:newPerson(inName)
Is equivalent to this:
function Person.newPerson(self, inName)
Therefore, when you do this:
Person.newPerson("Frank");
You are passing one parameter to a function that expects two. You probably don't want newPerson to be created with :.
Try
Frank = Person:newPerson("Frank");