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Difference between revisions of "mirc/identifiers/$null"
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| − | {{mirc title|$null | + | {{mirc title|$null identifier}}'''$null''' does not return a value; just like {{mIRC|$true}} or {{mIRC|$timeout}}, it's a value you can use in comparison in {{mIRC|/if}} or {{mIRC|/while}}. An empty variable also returns '''$null'''. |
| + | |||
== Synopsis == | == Synopsis == | ||
<pre>$null</pre> | <pre>$null</pre> | ||
| − | == | + | == Parameters == |
| − | |||
None | None | ||
== Properties == | == Properties == | ||
| − | |||
None | None | ||
== Example == | == Example == | ||
| + | |||
| + | If you created an empty variable without assigning a value, then you can check its existence and emptiness like this: | ||
| + | <source lang="mIRC"> | ||
| + | set %somevar | ||
| + | if ($var(%somevar)) echo -a This variable exists. | ||
| + | if (%somevar == $null) echo -a This variable is empty and has no value. | ||
| + | </source> | ||
| + | |||
| + | |||
<source lang="mIRC">//if ($? != $null) echo -a you entered $v1</source> | <source lang="mIRC">//if ($? != $null) echo -a you entered $v1</source> | ||
== Compatibility == | == Compatibility == | ||
| − | {{mIRC compatibility| | + | {{mIRC compatibility|4.5}} |
| − | == See | + | == See also == |
| − | {{mIRC|$false}} | + | * {{mIRC|$false}} |
| − | {{mIRC|$true}} | + | * {{mIRC|$true}} |
| − | [[Category: | + | * {{mIRC|$var}} |
| + | * {{mirc|identifiers|List of identifiers}} | ||
| + | {{mIRC identifier list}} | ||
| + | [[Category:mIRC identifiers|null]] | ||
Latest revision as of 17:14, 21 February 2024
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$null does not return a value; just like $true or $timeout, it's a value you can use in comparison in /if or /while. An empty variable also returns $null.
Synopsis[edit]
$null
Parameters[edit]
None
Properties[edit]
None
Example[edit]
If you created an empty variable without assigning a value, then you can check its existence and emptiness like this:
set %somevar if ($var(%somevar)) echo -a This variable exists. if (%somevar == $null) echo -a This variable is empty and has no value.
//if ($? != $null) echo -a you entered $v1
Compatibility[edit]
Added: mIRC v4.5
Added on: 30 Jun 1996
Note: Unless otherwise stated, this was the date of original functionality.
Further enhancements may have been made in later versions.
See also[edit]
mIRC identifier list