a && b: Difference between revisions

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|descr= Returns [[true]] only if both conditions are [[true]].
|descr= Returns [[true]] only if both conditions are [[true]].
In case of the alternative syntax, {{Wikipedia|Lazy_evaluation#Control_structures|lazy evaluation}} is used - if left operand is [[false]], evaluation of the right side is ignored.
In case of the alternative syntax, {{Link|https://en.wikipedia.org/wiki/Lazy_evaluation#Control_structures|lazy evaluation}} is used - if left operand is [[false]], evaluation of the right side is ignored.


|alias= [[a and b]]
|alias= [[a and b]]
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|s1= booleanA [[a && b|&&]] booleanB
|s1= booleanA [[a && b|&&]] booleanB


|p1= booleanA: [[Boolean]] - Test condition or variable
|p1= booleanA: [[Boolean]] - test condition or variable


|p2= booleanB: [[Boolean]] - Test condition or variable
|p2= booleanB: [[Boolean]] - test condition or variable


|r1= [[Boolean]]
|r1= [[Boolean]]
Line 45: Line 45:
|s2since= arma2oa 1.62
|s2since= arma2oa 1.62


|p21= boolean: [[Boolean]] - Test condition or variable
|p21= boolean: [[Boolean]] - test condition or variable


|p22= code: [[Code]] - Code that once executed returns a [[Boolean]]. The code is not evaluated if '''boolean''' is [[false]].
|p22= code: [[Code]] - code that once executed returns a [[Boolean]]. The code is not evaluated if '''boolean''' is [[false]].


|r2= [[Boolean]]
|r2= [[Boolean]]


|x1= <code>[[private]] _allEnemiesKilled = [[true]];
|x1= <sqf>private _allEnemiesKilled = true;
[[if]] ([[alive]] [[player]] && _allEnemiesKilled) [[then]]
if (alive player && _allEnemiesKilled) then
{
{
[[hint]] "you win !";
hint "you win !";
};</code>
};</sqf>


|x2= <code>if (([[count]] _array > 0) && { (_array [[select]] 0) == [[player]] }) [[then]] // an error would be thrown without lazy evaluation
|x2= <sqf>if ((count _array > 0) && { (_array select 0) == player }) then // an error would be thrown without lazy evaluation
{
{
[[hint]] "It works!";
hint "It works!";
};</code>
};</sqf>


|x3= <code>if (([[alive]] [[player]]) && { [[player]] [[setDamage]] 0.5; [[true]] }) [[then]] // valid '''as long as''' the code block returns a [[Boolean]]
|x3= <sqf>if ((alive player) && { player setDamage 0.5; true }) then // valid AS LONG AS the code block returns a Boolean
{
{
[[hint]] "It works!";
hint "It works!";
};</code>
};</sqf>


|seealso= [[and]] [[or]] [[Operators]]
|seealso= [[and]] [[or]] [[Operators]]
}}
}}

Latest revision as of 16:50, 8 November 2023

Hover & click on the images for description

Description

Description:
Returns true only if both conditions are true. In case of the alternative syntax, lazy evaluation is used - if left operand is false, evaluation of the right side is ignored.
Alias:
a and b
Groups:
VariablesMath

Syntax

Syntax:
booleanA && booleanB
Parameters:
booleanA: Boolean - test condition or variable
booleanB: Boolean - test condition or variable
Return Value:
Boolean

Alternative Syntax

Syntax:
boolean && code
Parameters:
boolean: Boolean - test condition or variable
code: Code - code that once executed returns a Boolean. The code is not evaluated if boolean is false.
Return Value:
Boolean

Examples

Example 1:
private _allEnemiesKilled = true; if (alive player && _allEnemiesKilled) then { hint "you win !"; };
Example 2:
if ((count _array > 0) && { (_array select 0) == player }) then // an error would be thrown without lazy evaluation { hint "It works!"; };
Example 3:
if ((alive player) && { player setDamage 0.5; true }) then // valid AS LONG AS the code block returns a Boolean { hint "It works!"; };

Additional Information

See also:
and or Operators

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