Returns TRUE if the input value is NULL (not the same as 0).
input|null()
TRUE or FALSE.
This operator returns TRUE if the input value is NULL, otherwise FALSE will be returned. Please note that NULL is not the same as a numeric zero (0).
{if 0|null()}
The truth is out there.
{else}
The day the earth stood still.
{/if}The following output will be produced: "The day the earth stood still".
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Comments (1 historical)
Written by readers of the earlier documentation sites, kept as they were.
is_null( null() )
André R. ·
As becomes clear when you read this page, is_null( null() ) will never work since null() and is_null() does the same, checks if input is null.
In other words there are no way of setting a variable to NULL in templates, it has to come from php ( fetch function or template operator ).