if: Difference between revisions

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(made clear it is a operator on it's own)
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| The standard if, then, else construct available in many languages. This syntax however has alternate forms in the manner of an [[Array]].
| This operator creates a [[If Type]] which is used in the if-construct as described [https://community.bistudio.com/wiki/Control_Structures#if-Statement here]. |= Description
* <tt>if (condition) then { code } else { code }</tt>
* <tt>if (condition) then [ { code }, { code } ]</tt>
Result of the [[Code]] executed is returned as the result to this command (which may be [[Nothing]]}. |= Description
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| [[Anything]] <nowiki>=</nowiki> '''if''' (condition) '''then''' { [[Code]] } '''else''' { [[Code]] } |= Syntax
| '''if''' condition |= Syntax


|p1= condition: [[Boolean]] expression. If it evaluates as 'true', the 'then' clause is executed.  Otherwise, the 'else' clause (if present) is executed. |= Parameter 1
|p1= condition: [[Boolean]] expression. If it evaluates as 'true', the 'then' clause is executed.  Otherwise, the 'else' clause (if present) is executed. |= Parameter 1


| [[If Type]] - Predicate which will execute 1st or 2nd option when used. This predicate is used in [[then]] or [[exitWith]] commands. |= Return value
| [[If Type]] - Predicate which will execute 1st or 2nd option when used. This predicate is used in [[then]] or [[exitWith]] commands. |= Return value
|s2= [[Anything]] <nowiki>=</nowiki> '''if''' (condition) '''then'''  '''[''' { ThenCode } ''',''' { ElseCode } ''']''' |= Alternative Syntax
|p21= condition: [[Boolean]] expression. If it evaluates as 'true', the 'then' clause is executed.  Otherwise, the 'else' clause (if present) is executed. |= Alternative Parameter 1
|r2= [[If Type]] - Predicate which will execute 1st or 2nd option when used. This predicate is used in [[then]] or [[exitWith]] commands. |= Alternative Return value
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Revision as of 12:53, 3 January 2017

Hover & click on the images for description

Description

Description:
This operator creates a If Type which is used in the if-construct as described here.
Groups:
Uncategorised

Syntax

Syntax:
if condition
Parameters:
condition: Boolean expression. 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:
_retVal = if (1 > 0) then { "It's true" } else { "It's false" }; hint str _retVal
Example 2:
_val = if (true) then [ { "true" }, { "false" } ]; hint _val;

Additional Information

See also:
elseexitWiththenControl Structures

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

Notes

Posted on Jan 31, 2007 - 04:08
Ceeeb
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
Galzohar
(A2 1.05) 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: hint "script started"; //will get executed if (nil) then { hint "true"; // will never get executed } else { hint "false"; // will never get executed }; sleep 3; hint "script ended"; //will get executed

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Posted on June 5, 2015 - 09:35 (UTC)
AgentRevolution
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: _result = [falseValue, trueValue] select condition; 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: _result = [1,-1] select (_this < 0); // If _this is less than 0, _result will be equal to -1, otherwise it will be 1 This feature was added in Arma 3.