SQF Syntax: Difference between revisions

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     Command 4;  
     Command 4;  
  };
  };
===Operation Flashpoint===
SQF syntax was introduced for the first time with the [[call]] command in Operation Flashpoint. Usage was limited to execution of [[Function|functions]].
===Armed Assault===
With the release of Armed Assault, the SQS syntax for scripting was deprecated. SQF syntax is expected to be used for both scripts and [[Function|functions]].
[[sqs syntax|SQS syntax]] is compiled line-by-line as it is executed. SQF files must be compiled ahead of time and are thus more efficient at time of execution. SQF scripts are compiled and executed with either the [[execVM]] command or manually via [[compile]] and [[spawn]]. Since scripts run parallel with each other, you must use [[scriptDone]] if you wish to have a ''calling'' script wait for a ''called'' script to finish.
<br>
'''Diagram of Scripts Running in Parallel'''
[[Image:ParallelSQFScript.jpg]]
<br>
'''Diagram of Scripts Running in Parallel using [[waitUntil]] and [[scriptDone]] to pause execution'''
[[Image:ParallelSQFScript_WaitUntil.jpg]]
<br>


==Language Constructs==
==Language Constructs==

Revision as of 15:04, 21 December 2006

SQF syntax was introduced in Operation Flashpoint: Resistance and is the common syntax since Armed Assault. An alternative syntax is the SQS syntax (deprecated since Armed Assault).

While SQS syntax is line based, SQF syntax is based on structured expressions. End-of-line has no special meaning - it is considered to be equivalent to space or tab, and is therefore not required, even when ending a statement.

Rules

Binding rules:

  • Curled braces group code to blocks
  • Commands and blocks are followed by semicolons

The latter rule tells the game engine where one command ends and the next starts.

Example:

Command 1;
Command 2;

Block
{
    Command 3;
    Command 4; 
};

Language Constructs

Main language contructs used in functions are:

Notes

Due to line-based nature of Sqs scripts it is not possible to create multiline string constants in them.
To overcome this limitation you can store multiline in separate SQF function files and load them using loadFile or preprocessFile (the second uses C-like preprocessor with // or /* */ comments and #define macros).

See also

Commands

Function