isNil: Difference between revisions
| Lou Montana (talk | contribs) m (Text replacement - "\{\{( *)Informative( *)\|" to "{{$1Feature$2|$2Informative$2|") | Lou Montana (talk | contribs)  m (Text replacement - "\| *((\[\[[a-zA-Z0-9_ |()]+\]\],? ?)+) * \}\}" to "|seealso= $1 }}") | ||
| Line 47: | Line 47: | ||
| [[if]] ([[format]] ["%1", foo] == _nil) [[then]] { foo = "value"; };</code> | [[if]] ([[format]] ["%1", foo] == _nil) [[then]] { foo = "value"; };</code> | ||
| | [[nil]], [[Variables]], [[Scheduler]] | |seealso= [[nil]], [[Variables]], [[Scheduler]] | ||
| }} | }} | ||
Revision as of 23:48, 16 February 2021
Description
- Description:
- Description needed
- Groups:
- Variables
Syntax
- Syntax:
- Syntax needed
- Parameters:
- variableName: String - name of a missionNamespace variable (e.g "someVar") or a local variable (e.g "_someVar")
- Return Value:
- Return value needed
Alternative Syntax
- Syntax:
- isNil code
- Parameters:
- code: Code - code to evaluate:
- the code will be executed; isNil { player setDamage 1; };will kill the player
- the code will not be allowed to suspend while expression is evaluated, even if the parent scope allows it (see Example 4).
 
- the code will be executed; 
- Return Value:
- Boolean - true if code returns something other than Nothing
Examples
- Example 1:
- if (isNil "pokus") then { pokus = 0; };
- Example 2:
- isNil { player getVariable "someVar" };
- Example 3:
- _myArray = [0, 1]; isNil { _myArray select 0 }; // returns false isNil { _myArray select 1 }; // returns false isNil { _myArray select 2 }; // returns true isNil { _myArray select 3 }; // throws a script error. only length+1 select is allowed
- Example 4:
- You can do this trick to force execute something in Unscheduled Environment.spawn { systemChat str canSuspend; // chat shows true isNil {hint str canSuspend}; // hint shows false };
- Example 5:
- Operation Flashpoint workaround:
 SQS syntax:_nil = format ["%1", _undefinedVariable] ? (format ["%1", foo] == _nil) : foo = "value"SQF syntax:_nil = format ["%1", _undefinedVariable]; if (format ["%1", foo] == _nil) then { foo = "value"; };
Additional Information
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
