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Game will display 2.<br><br>
Game will display 2.<br><br>
Inserting <i>private "_a"</i> in the function prevents the change and so number 1 will be displayed on the screen.
Inserting <i>private "_a"</i> in the function prevents the change and so number 1 will be displayed on the screen.
<dd class="notedate">Posted on February 25, 2015 - 17:06 (UTC)</dd>
<dt class="note">[[User:DreadedEntity|DreadedEntity]]</dt>
<dd class="note">
Recursive loops require the use of [[private]]. Without it, your variables will be overwritten.
</dd>
<dd class="notedate">Posted on January 31, 2018 - 10:30 (UTC)</dd>
<dt class="note">Dscha</dt>
<dd class="note">More examples!<br>
<code>[[if]] ([[true]]) [[then]] { //new scope
_localVar = "some string";
[[systemChat]] _localVar; // = "some string"
};
[[systemChat]] _localVar; // = ERROR _localVar doesn't exist in the outer Scope
</code>
<code>_localVar = "bla";
[[if]] ([[true]]) [[then]] { //new scope
_localVar = "some string";
[[systemChat]] _localVar; // = "some string"
};
[[systemChat]] _localVar; // = "some string"
</code>
<code>_localVar = "bla";
[[if]] ([[true]]) [[then]] {
[[private]] _localVar = "some string";
[[systemChat]] _localVar; // = "some string"
};
[[systemChat]] _localVar; // = "bla"
</code>
<code>_localVar = "bla";
[[if]] ([[true]]) [[then]] { //new scope
[[private]] _localVar = "some string";
[[if]] ([[true]]) [[then]] { //new scope
[[private]] _localVar = "some other string";
[[systemChat]] _localVar; // = "some other string"
};
[[systemChat]] _localVar; // = "some string"
};
[[systemChat]] _localVar; // = "bla"
</code>
</dd>
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<dl class="command_description">
<dl class="command_description">
<dd class="notedate">Posted on February 25, 2015 - 17:06 (UTC)</dd>
<dd class="notedate">Posted on January 31, 2018 - 10:37 (UTC)</dd>
<dt class="note">[[User:DreadedEntity|DreadedEntity]]</dt>
<dt class="note">[[User:654wak654|654wak654]]</dt>
<dd class="note">
<dd class="note">
Recursive loops require the use of [[private]]. Without it, your variables will be overwritten.
This command has the same functionality as javascript's let keyword.<br>
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let
</dd>
</dd>
</dl>
</dl>
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Revision as of 12:37, 31 January 2018

Hover & click on the images for description

Description

Description:
Sets a variable to the innermost scope as demonstrated in Example 3. One other command that is capable of creating private variables is params.
Since Arma 3 v1.53.132932 private can be used as keyword as shown in Example 4.
Groups:
Uncategorised

Syntax 1

Syntax:
private variableName
Parameters:
variableName: String
Return Value:
Nothing

Syntax 2

Syntax:
private variableNameList
Parameters:
variableNameList: Array of Strings
Return Value:
Nothing

Syntax 3

Syntax:
private variable = value         (Since Arma 3 v1.53.132932)
Parameters:
variable: underscored variable, for example _myvar
value: Anything: value to assign to the variable
Return Value:
Nothing

Examples

Example 1:
private "_varname";
Example 2:
private ["_varname1", "_varname2"];
Example 3:
_myvar = 123; systemChat str [_myvar]; // -- [123] call { systemChat str [_myvar]; // -- [123] private "_myvar"; systemChat str [_myvar]; // -- [any] _myvar = 345; systemChat str [_myvar]; // -- [345] }; systemChat str [_myvar]; // -- [123]
Example 4:
Usage of private as keyword: private _myvar = 123; //is the same as private "_myvar"; _myvar = 123;
Example 5:
_lol = 123; call {hint str [_lol]}; // [123] _lol = 123; call {private "_lol"; hint str [_lol]}; // [any]

Additional Information

See also:
paramsScope

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 Sep 24, 2009 15:04
ColonelSandersLite

The example provided is fairly worthless without a context.
Using the private command allows you to declare a variable in the current scope, without regards to variables in a higher scope with the same name. Note that if you try to declare a variable without an underscore (meaning it's global) with the private command, it will cause an error. Specifically: "Error Local variable in global space".
Here's a code example with output for your benefit.
_foo = 10; if (true) then { private ["_foo"]; _foo = 5; player sideChat format ["%1", _foo]; }; player sideChat format ["%1", _foo]; In this example, the first sidechat (innermost) returns 5 while the second sidechat (outermost) returns 10.
if (true) then { private ["_bar"]; _bar = 5; player sideChat format ["%1", _bar]; }; In this example, the private command does nothing and is simply a waste of code, assuming there is no higher level code to interfere with the if statement.
Posted on August 4, 2010
Faguss
The higher scope is also the script from which the function has been called.
If you've got in the script: _a = 1; call compile loadFile "function.sqf"; hint format ["%1", _a]; And in the function.sqf: _a = 2; Game will display 2.

Inserting private "_a" in the function prevents the change and so number 1 will be displayed on the screen.
Posted on February 25, 2015 - 17:06 (UTC)
DreadedEntity
Recursive loops require the use of private. Without it, your variables will be overwritten.
Posted on January 31, 2018 - 10:30 (UTC)
Dscha
More examples!
if (true) then { //new scope _localVar = "some string"; systemChat _localVar; // = "some string" }; systemChat _localVar; // = ERROR _localVar doesn't exist in the outer Scope _localVar = "bla"; if (true) then { //new scope _localVar = "some string"; systemChat _localVar; // = "some string" }; systemChat _localVar; // = "some string" _localVar = "bla"; if (true) then { private _localVar = "some string"; systemChat _localVar; // = "some string" }; systemChat _localVar; // = "bla" _localVar = "bla"; if (true) then { //new scope private _localVar = "some string"; if (true) then { //new scope private _localVar = "some other string"; systemChat _localVar; // = "some other string" }; systemChat _localVar; // = "some string" }; systemChat _localVar; // = "bla"

Bottom Section

Posted on January 31, 2018 - 10:37 (UTC)
654wak654
This command has the same functionality as javascript's let keyword.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let