How to replace a block of code

[Lauriel]

I am trying to set up a TP2 file for a mod I'm working on.  The first thing I need to do is replace a block of code from an area script file.  I'm trying to use REPLACE_BCS_BLOCK, but nothing happens except I get the can't-find-block error at the end.

Here's what the TP2 file looks like so far:
 

Spoiler

 

BACKUP ~my_mod/backup~
AUTHOR ~me@url.com~

BEGIN ~My Mod V0.1~

COPY_EXISTING ~BGareafile.BCS~ ~my_mod/wip/BGareafile.BCS~
    DECOMPILE_AND_PATCH BEGIN
        REPLACE_BCS_BLOCK ~my_mod/wip/Old_blockcode.baf~ ~my_mod/wip/New_blockcode.baf~ ON_MISMATCH PATCH_FAIL ~Couldn't find block to replace~ END
    END

BUT_ONLY_IF_IT_CHANGES

 

NOTE: I'm playing with the file in a separate WIP folder instead of the normal override folder because I don't want to mess up my game. 

Contents of decompiled BGareafile.BAF
 

Spoiler

 

<some code block>

IF
  Dead("targetnpc")  // ~target npc~
  Global("some global I don't care about","GLOBAL",0)
THEN
  RESPONSE #100
    do something I want to stop
    do something else I want to skip
    and a whole list of things I want to skip
END

<many other code blocks>

 

Contents 0f Old_blockcode.baf:

Spoiler

IF
  Dead("targetnpc")  // ~target npc~
  Global("some global I don't care about","GLOBAL",0)
THEN
  RESPONSE #100
    do something I want to stop
    do something else I want to skip
    and a whole list of things I want to skip
END

 

Contents of New_codeblock.baf

Spoiler

IF
  Dead("targetnpc")  // ~target npc~
  Global("some new global","GLOBAL",0)
THEN
  RESPONSE #100
    SetGlobal("some new global","GLOBAL",1)

END

 

Anyway, am I not using REPLACE_BCS_BLOCK correctly?

Edited December 24, 2019 by Lauriel
Added pseudo code of code block files

[jastey]

This is tricky as the installer is very sensitive (e.g. formatting, missing spaces etcpp). With REPLACE_TEXTUALLY you have a finer handling of what exactly you want to replace. (If necessary, whole blocks can be deaxtivated by putting a False() as a trigger).

It's also better compatibility wise than replacing a whole block.

I'll post examples soon or you could have a look into my Imoen4Ever mod (for which I stole it from eet).

[jastey]

Hm, in your example maybe just placing another block of code in front of the original one would work, too. You'd need to set the original variable, too, to deactivate the original code block. If that's possible without triggering / preventing other events.

[Guest Lauriel]

I see what you're saying.  Instead of trying to replace the block, insert one in ahead of it and break the old one.  It grates against my pedantic programming sensibilities, but I see the benefit. It would certainly make it easier to undo the change in the future.  It would almost like commenting out the offending block, which is something I miss.

Thank you for the out-of-the-box solution.   I like it!

[Lauriel]

Not 'out-of-the-box', should be 'outside-the-box'.  LOL  So funny.  Sorry!

[jastey]

I'M ESL so I didn't even notice.

12 hours ago, Guest Lauriel said:

Instead of trying to replace the block, insert one in ahead of it and break the old one.  It grates against my pedantic programming sensibilities, but I see the benefit.

As I said, it depends on what you want to do (and whether you can change the original variable without causeing any unwanted changes), but seeing your script blocks I had the impression you more or less wanted to get rid of a whole block in the original game, so this is also the more stable way of achieving it. (EDIT: stable in the meaning of REPLACE_xx might fail in the player's game).

One note, though: if you do EXTEND_TOP to scripts, always add an Continue() at the end of your code block - because it might be there is an OnCreation() one already there (or added by a mod). This is advice from the depth of the modding community from painful experience why area scripts don't do what they are supposed to be..

[Luke]

Moreover, you might want to look at these functions...

[Lauriel]

Thank you, @Luke!  Those look like they'd absolutely do the trick.  Although in this instance I'll use @jastey's suggestion, I'll certainly keep these other beauties in mind.

Thanks again!

 

[Lauriel]

Ok, I reevaluated my plan of attack.  @Luke, those functions are a thing of beauty.  Thank you so much for pointing them out.  

[Lauriel]

Well, I'd like to use them, but I'm such a newb that I can't seem to figure out how.  Here's what I have and I get a parsing error

Spoiler

BACKUP ~transitions/backup~
AUTHOR ~lzenner@live.com~
VERSION ~0.1~

README ~transitions/readme.transitions.%LANGUAGE%.txt~ ~transitions/readme.transitions.english.txt~

AUTO_TRA ~transitions/languages/%s~

ALWAYS
   ACTION_IF NOT GAME_IS ~eet~ BEGIN
      FAIL @1
   END

   ACTION_DEFINE_ARRAY Transitions_noconvert BEGIN setup END
   ACTION_DEFINE_ARRAY Transitions_reload BEGIN game dialogues END

   LAF HANDLE_CHARSETS
      INT_VAR
         infer_charset = 1
      STR_VAR
         tra_path = EVAL ~transitions/language~
         noconvert_array = Transitions_noconvert
         reload_array = Transitions_reload
   END
   
   // CamDawgs CD_STATE_NOTVALID
   APPEND ~STATE.IDS~ ~0x80101FEF CD_STATE_NOTVALID~ UNLESS ~CD_STATE_NOTVALID~

   INCLUDE ~transitions/lib/alter_script.tpa~                        <========== This is how I included the library - is this not correct?
END

LANGUAGE ~American English~ ~english~   
   ~transitions/languages/english/setup.tra~
   ~transitions/languages/english/game.tra~

////////////////////////////////////////////////////////////////////
// MAIN COMPONENT: ALLOW CONTINUED PLAY AFTER SAREVOK IS DEFEATED //
////////////////////////////////////////////////////////////////////
BEGIN @3
// This option removes the movie from the end of the fight
// so it can be used in a dream sequence later on
FORCED_SUBCOMPONENT @2
INSTALL_BY_DEFAULT
COPY_EXISTING ~BG0125.BCS~ ~override~
   DECOMPILE_AND_PATCH BEGIN
      COUNT_REGEXP_INSTANCES ~Global("C#st_BG1End","GLOBAL",0)~ endlessPatchInstalled
      PATCH_IF (endlessPatchInstalled > 0) BEGIN
         // Don't play the movie after the fight
         LAF REPLACE_SCRIPT_BLOCK                   <============= This gives the parsing error - is this not how you use these?
            INT_VAR
               only_once = 1
            STR_VAR
               script = BG0125                     <============= the examples didn't have the script file inside tildes ... assume this is ok
               match = ~C#st_BG1End~
               insert = ~transitions/scripts/New0125a.baf~
         END
         // Replace the block where jastey spawns her flaming fist healers
         LAF REPLACE_SCRIPT_BLOCK
            INT_VAR
               only_once = 1
            STR_VAR
               script = ~BG0125~
               match = ~C#st_FFHealerSpawn","GLOBAL",0)~
               insert = ~transitions/scripts/New0125c.baf~
         END
      END ELSE BEGIN
         LAF REPLACE_SCRIPT_BLOCK
            INT_VAR
               only_once = 1
            STR_VAR
               script = ~BG0125~
               match = ~Dead("Sarevok")~
               insert = ~transitions/scripts/New0125a.baf~
         END
         APPEND_FILE TEXT ~transitions/scripts/New0125c.baf~
      END
   END
BUT_ONLY_IF_IT_CHANGES

 

 

[Lauriel]

Nevermind once again - I figured it out.