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The JASS2 Script
This is the main map script file. It's a text file and you can open it with notepad.
The language used is called JASS2 and has been developped by Blizzard. It's a case sensitive language.
When you play a map, the jass script is loaded and executed. To run it, Warcraft III looks for the function called "main".
The language uses several keywords as described here:
| Keyword
| Description
|
| function
| used to define a new fonction
|
| takes
| used to define the number of arguments for a fontction
|
| returns
| sets the type of the value returned by a function
|
| return
| makes a function leaves and returns a value
|
| endfunction
| ends a function definition
|
| call
| used to call a function that returns nothing
|
| globals
| used to define the list of global variables
|
| endglobals
| ends the list of global variables definition
|
| local
| defines a local variable
|
| set
| assigns a value to a variable
|
| if, elseif, else, then, endif
| if (...) then ...
elseif (...) then ...
else ...
endif
Just an "if-then-else-endif" chain like in Basic.
|
| loop, exitwhen, endloop
| used to make loops in the script
|
| constant
| defines a constant
|
| type
| defines a new type/class
|
| extends
| says what the mother type is
|
| native
| defines a function header of an external built-in function implemented in Game.DLL
|
Only two "native types" exists: "nothing" and "handle". All the other types are derived (keyword "extends") from "handle". You can get the full list of types and native functions from the file called "Scripts\Common.j" in your War3.mpq file. You can assign several types of constant values to the handle type: a generic null value called "null", any interger, any float, any string or trigger string, "true" and "false".
Here is the list of operators recognized by the language:
| Operator
| Description
|
| ( )
| parenthesis for priorities
|
| +
| addition (concatenation for strings)
|
| -
| substraction
|
| *
| multiplication
|
| /
| division
|
| =
| assignation
|
| = =, <, <=, >, >=, !=
| comparison (equal, lighter, lighter or equal, greater, greater or equal, different)
|
| not
| invert a boolean value
|
The functions used by the World Editor are defined in "Scripts\Blizzard.j".
Example of a function definition:
function myfunction takes nothing returns integer
local string str = "blah blah blah"
local integer i
// comments line
set i = 0
loop
set i = i + 1
if (i == 27) then
call DisplayTimedTextToPlayer(GetLocalPlayer(), 0, 0, 60, str)
endif
exitwhen i == 30
endloop
return i
endfunction