Text Parser error: Too many nested if/else statements

[jmjm]

Hi, all!

I'm making a text parser game and while writing my global parser commands I've finally gotten the error "too many nested if/else statements". Unfortunately I'm not even close to writing all my parser commands for my game!

I read a post with a similar issue http://www.adventuregamestudio.co.uk/forums/index.php?topic=41044.0 and I tried making separate functions for my text parser function to split up how many if/else statements are in each, but I can't seem to make the game parse the text beyond the first function.

I tried having my first text parser function have an else statement that stores the String text like so:

Code: ags

else
    input2 = input1;

and then have the following function include:

Code: ags

if (input2 == input1)
{
    Parser.ParseText(input2);

        if (Parser.Said("eat apple."))
            {
              Display("Yummy!");
            }

        else if (Parser.Said("eat orange."))
            {
              // etc.
            }

        else
            CallRoomScript(1);
}

But that doesn't seem to do anything. The game runs and recognizes the parses in the first function, but nothing in the second function, nor does it call the room script. When running the game, when I enter "eat apple" the game returns nothing and no error message, just continues to run as before.

I'm self-taught so apologies if I've asked something dumb or didn't format the stuff right. The code sections aren't copy-pasted in, I'm just showing the basic stuff in hopes that it makes things easier to see.

Any help (or suggestions of game engines that would be better suited!) would be much appreciated!

[Snarky]

I've never actually used the AGS parser, but I'm pretty sure the problem is here:

Code: ags

else
    input2 = input1;

I'm not sure quite what you're trying to do here, but it doesn't look right.
(You already have the string as input1; you don't need another copy of it. If you just want to keep track of whether something is true or false, use a bool flag.)

This bit also looks pretty dodgy:

Code: ags

if (input2 == input1)
{
    Parser.ParseText(input2);

The issue here is that it looks like you're calling Parse.ParseText() a second time. There's really no point, if you've already run it with input1. The Parser won't reset itself until you call it with some other argument, and it could even conceivably be that calling the parser twice in a single cycle might break it.

(Edit: D'oh! How did I miss that? The immediate cause of the error is that you can't use == to compare two strings. Still, I think the solution suggested here is better than just changing it to String.CompareTo().)

First of all: Do you really need the nested if/else-ifs? Presumably there's only one case that will return true for the Parser.Said() tests, so you could really just have a long list of if statements, without any elses. The only problem would be the final CallRoomScript() fallback, but you could always set a flag for whether it should run or not.

Here's another alternative, which is how I might structure the code:

Code: ags

bool parse1()
{
  if(Parser.Said("eat apple")
  {
    Display{"Yummy!");
  }
  else if(Parser.Said("eat orange")
  {
    // ...
  }
  // other cases
  else
    return false;
  return true;
}

bool parse2()
{
  // Same structure as parse1()
}

// parse3(), parse4(), etc. As many as you need

// Place in the script where you check the parser:
{
  // ...
  Parser.ParseText(input1);
  if(!parse1() && !parse2()) // etc.
  {
    CallRoomScript(1);
  }
}

[Crimson Wizard]

Edit: D'oh! How did I miss that? The immediate cause of the error is that you can't use == to compare two strings.

You can, AGS supports this operator for strings. That is mentioned in CompareTo manual entry.

[Snarky]

Ah bugger! I even had a whole long argument about that (and why I think it's a bad idea) a while ago.

In my defense, it was almost 4 in the morning when I wrote that...

[jmjm]

Hooray!

Snarky, I tried your suggestion on how to structure the code and it worked like a charm. I'd been struggling for days!

Thanks for the feedback, folks. Very much appreciated. Massive sigh of relief!