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Lou Montana (talk | contribs) m (Text replacement - "<sqf>([^↵][^<]*↵[^<]*)<\/sqf>" to "<sqf> $1 </sqf>") |
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{{ | {{RV|type=command | ||
| | |game1= ofp | ||
|version1= 1.85 | |||
|1. | |game2= ofpe | ||
|version2= 1.00 | |||
| | |game3= arma1 | ||
|version3= 1.00 | |||
| | |game4= arma2 | ||
|version4= 1.00 | |||
| | |game5= arma2oa | ||
| | |version5= 1.50 | ||
| | |game6= tkoh | ||
|version6= 1.00 | |||
|game7= arma3 | |||
|version7= 0.50 | |||
|gr1= Program Flow | |||
|descr= This operator creates a [[If Type]] which is used in the if-construct as described [[Control_Structures#if-Statement|here]]. | |||
|s1= [[if]] condition | |||
|p1= condition: [[Boolean]] - if it evaluates as [[true]], the [[then]] clause is executed. Otherwise, the [[else]] clause (if present) is executed | |||
|r1= [[If Type]] - predicate which will execute 1st or 2nd option when used. This predicate is used in [[then]] or [[exitWith]] commands | |||
|x1= <sqf> | |||
_retVal = if (1 > 0) then { "It's true" } else { "It's false" }; | |||
hint str _retVal; | |||
</sqf> | |||
|x2= <sqf> | |||
_val = if (true) then [{ "true" }, { "false" }]; | |||
hint _val; | |||
</sqf> | |||
|seealso= [[else]] [[exitWith]] [[then]] [[Control Structures]] [[Code_Optimisation#Lazy_evaluation|Lazy evaluation]] | |||
}} | |||
{{Note | |||
|user= Ceeeb | |||
Any variables you declare within the body of an if/[[then]] statement (ie between the curly braces) are local to that 'if' statement, and are destroyed at the end of the statement. If you know you want to use the variable outside the 'if' statement, make sure your declare it before the 'if' statement. | |timestamp= 20070131040800 | ||
|text= Any _local variables you declare within the body of an [[if]]/[[then]] statement (ie between the curly braces) are local to that 'if' statement, and are destroyed at the end of the statement. If you know you want to use the variable outside the 'if' statement, make sure your declare it before the 'if' statement. | |||
}} | |||
< | {{Note | ||
</ | |user= Galzohar | ||
|timestamp= 20100117024000 | |||
|text= If the condition is nil then neither the "then" nor the "else" section get executed, but the script will proceed with no error messages.<br> | |||
Example code: | |||
<sqf> | |||
systemChat "script started"; // will get executed | |||
if (nil) then | |||
{ | |||
systemChat "true"; // will never get executed | |||
} | |||
else | |||
{ | |||
systemChat "false"; // will never get executed | |||
}; | |||
systemChat "script ended"; // will get executed | |||
</sqf> | |||
|game= arma2 | |||
|version= 1.05 | |||
}} | |||
< | {{Note | ||
|user= AgentRev | |||
|timestamp= 20150605093500 | |||
|text= If you only need to choose between 2 raw values, it is possible to use the following trick to avoid using code blocks, as required by the if command, which results in greater atomicity and faster execution: | |||
<sqf>_result = [falseValue, trueValue] select condition;</sqf> | |||
The select command treats "false" as 0 and "true" as 1, therefore you can feed it a condition determining the array index of the value to be returned. Here is another example: | |||
<sqf>_result = [1,-1] select (_this < 0); // if _this is less than 0, _result will be equal to -1, otherwise it will be 1</sqf> | |||
}} | |||
{{Note | |||
|user= DreadedEntity | |||
|timestamp= 20220519011146 | |||
[[ | |text= When using '''if''' to assign values to a variable, if you not have an [[else]] block it is treated as [[nil]] and returned, setting the variable value to [[nil]]. A3 2.08.149102 | ||
[[ | <sqf> | ||
[[ | private _myVar = "value"; | ||
private _condition = false; | |||
_myVar = if (_condition) then { "another value" }; //perfectly valid sqf | |||
systemChat str (isNil "_myVar"); //returns true | |||
//_myVar is now nil | |||
_myVar = if (_condition) then { "another value" } else { "value" }; | |||
systemChat _myVar; //returns "value" | |||
</sqf> | |||
This behavior can be both desirable and undesirable depending on your needs | |||
}} |
Latest revision as of 19:43, 3 September 2024
Description
- Description:
- This operator creates a If Type which is used in the if-construct as described here.
- Groups:
- Program Flow
Syntax
- Syntax:
- if condition
- Parameters:
- condition: Boolean - if it evaluates as true, the then clause is executed. Otherwise, the else clause (if present) is executed
- Return Value:
- If Type - predicate which will execute 1st or 2nd option when used. This predicate is used in then or exitWith commands
Examples
- Example 1:
- Example 2:
Additional Information
- See also:
- else exitWith then Control Structures Lazy evaluation
Notes
-
Report bugs on the Feedback Tracker and/or discuss them on the Arma Discord or on the Forums.
Only post proven facts here! Add Note
- Posted on Jan 31, 2007 - 04:08 (UTC)
- Any _local variables you declare within the body of an if/then statement (ie between the curly braces) are local to that 'if' statement, and are destroyed at the end of the statement. If you know you want to use the variable outside the 'if' statement, make sure your declare it before the 'if' statement.
- Posted on Jan 17, 2010 - 02:40 (UTC)
-
If the condition is nil then neither the "then" nor the "else" section get executed, but the script will proceed with no error messages.
Example code:systemChat "script started"; // will get executed if (nil) then { systemChat "true"; // will never get executed } else { systemChat "false"; // will never get executed }; systemChat "script ended"; // will get executed
- Posted on Jun 05, 2015 - 09:35 (UTC)
- If you only need to choose between 2 raw values, it is possible to use the following trick to avoid using code blocks, as required by the if command, which results in greater atomicity and faster execution: The select command treats "false" as 0 and "true" as 1, therefore you can feed it a condition determining the array index of the value to be returned. Here is another example:
Categories:
- Scripting Commands
- Introduced with Operation Flashpoint version 1.85
- Operation Flashpoint: New Scripting Commands
- Operation Flashpoint: Scripting Commands
- Operation Flashpoint: Elite: Scripting Commands
- ArmA: Armed Assault: Scripting Commands
- Arma 2: Scripting Commands
- Arma 2: Operation Arrowhead: Scripting Commands
- Take On Helicopters: Scripting Commands
- Arma 3: Scripting Commands
- Command Group: Program Flow