Using EDL in LateralGM

[rotenKleber]

Okie Doke, I'm not really used to Enigma-Dev/LateralGM, so please don't beat me up if I should have known this.

I was happily making game, when I needed a well placed struct. Attempting to build the struct in a script that ran at the start of the game, I found that Enigma did not find my struct to mean anything

scr_init:

Code: [Select]

struct itemStats {
string itemID = "";
int amount = 1;
}

made

error:

Code: [Select]

Syntax error in script `scr_init'
Line 1, position 18 (absolute 17): Unterminated brace at this point

So is there some way I failed in implementing my EDL? Was a script a bad place to put it? Is my struct malformed?

[Goombert]

You are missing a semicolon and ENIGMA only allows structs in Definitions, please see the Wiki page.

http://enigma-dev.org/docs/Wiki/Structures

It is important to realize that structures and classes cannot be defined in EDL as with other code. They must be defined in Definitions, as with other C++ functions. Then they can be instantiated and used in your EDL code. In other words, the above example code could not be placed in, say, an object's Create event. It must go in Definitions.

You can find Definitions under Build->Settings->ENIGMA->General->Definitions Button

Though I did also try this myself and could not get it to work, it seems that the dot operator is broken.

Code: (edl) [Select]

itemStats stats;
stats.amount = 66;
if (stats.amount == 66) {
show_message(string("hello"));
}


Code: (edl) [Select]

struct itemStats {
string itemID = "";
int amount = 1;
};


error: invalid cast from type 'itemStats' to type 'int'
     if((enigma::varaccess_amount(int(stats))== 66))
                                           ^

[rotenKleber]

Aha, thank you very much. Those definitions are quite handy.

I was a bit confused with the final semicolon, as the example over at http://enigma-dev.org/docs/Wiki/ENIGMA:Specification says

struct circle {
  var x = 0, y = 0;
  double radius;
  double get_area() { return pi * radius * radius; } // Simple method
  circle(double r = 1) { radius = r }; // Optimizing this falls on the language plugin
  ~circle() { destroy_radius(x,y,radius); }
}

Without the final semicolon

[Goombert]

I just tested myself again, and it does want the semicolon in Definitions. I think we planned/plan to make the semicolon optional but never got around to it. Basically, our GML->C++ compiler is not run over Definitions right yet, so Definitions is just pure C++.

This I got to actually compile:

Code: (C++) [Select]

struct circle {
  var x = 0, y = 0;
  double radius;
  double get_area() { return pi * radius * radius; } // Simple method
  circle(double r = 1) { radius = r; }; // Optimizing this falls on the language plugin
  ~circle() { }
};


Code: (EDL) [Select]

circle *test = new circle();

test.x = 539;

show_message(string(test.x));

I'm surprised that new is required otherwise the dot operator does not work. That would be a question to ask Josh, but at least for now using structs like that works.

[rotenKleber]

Haha so I need to dynamically allocate all my structs? Do I also need to free them, then?
And the dot operator replaces the "->" operator?

Edit-
Okie Dokie I tried this in EDL

Code: [Select]

itemStats stats = new itemStats();

But alas

Code: [Select]

Line 8, position 34 (absolute 297): Unknown function or script `itemStats'


[Goombert]

No, you need the star, it's a C++ pointer.

Code: (EDL) [Select]

itemStats *stats = new itemStats();
You probably do need to delete them as well, but that would maybe be better answered by Josh. I would go ahead and delete them anyway.

[rotenKleber]

Oh my bad, I did have that asterisk in there.

Code: [Select]

itemStats *stats = new itemStats();

Perhaps this code cannot be implemented in scripts (EDL)? Can I only use that with C++ in definitions?

[Goombert]

That's weird, I used it in the create event, give me a minute and I'll test.

Edit: Just tested my code from above in a script and called it from create, worked fine. So let me test the struct you are using.

Edit 2: Nope, I just tested again, it worked fine for me.

Definitions

Code: (EDL) [Select]

struct itemStats {
        string itemID = "";
        int amount = 1;
};

scr_0

Code: (EDL) [Select]

itemStats *test = new itemStats();

test.amount = 539;

show_message(string(test.amount));

Create event:

Code: (EDL) [Select]

scr_0();


[rotenKleber]

Strange, I tried your exact examples, and got this error:

Code: [Select]

.h:40:36: error: cast from ‘itemStats*’ to ‘int’ loses precision [-fpermissive]
   enigma::varaccess_amount(int(test))= 539;
                                    ^
/home/kleber/.enigma/Preprocessor_Environment_Editable/IDE_EDIT_objectfunctionality.h:41:58: error: cast from ‘itemStats*’ to ‘int’ loses precision [-fpermissive]
   show_message(toString(enigma::varaccess_amount(int(test))));


[Goombert]

Ahhhh, I bet I know why, are you on Linux? (I see your penguin). If so, then you are probably using GCC which is a little different than the MinGW I am using on Windows.

You could try making the cast explicit:

Code: (EDL) [Select]

test.amount = (int)539;
Or just change amount from int to var in the struct.

[rotenKleber]

Ah, yes, I am on GNU/Linux

Hm, neither of those fixed it. Would it work if I used a different compiler?

[Goombert]

Try using -> instead of the . operator. Definitely do not try using a different compiler, we want GCC to work, GCC is the defacto. For now anyway.

[rotenKleber]

That results in the

Code: [Select]

Syntax error in script `scr_0'
Line 3, position 6 (absolute 43): Expected primary expression before operator


[Goombert]

Shoot, I'm about out of ideas until Josh gets here to ask. He should be here later tonight.

What is the output of gcc -v in a terminal?

[Goombert]

Oh I think I know what the problem is thanks to Rusky. I do not think we turned on C++11 for Linux yet. Try using this rewritten struct, c++98 does not support default values like that.

Code: (EDL) [Select]

struct itemStats {
  string itemID;
  int amount;

  itemStats() : itemID(""), amount(1) { }
};