Summary

Usage

input|is_null( target )

Parameters

Returns

Description

This operator checks if the input parameter or the target variable is NULL. If it is, the operator will return TRUE, otherwise FALSE will be returned. If both the input parameter and the target variable are provided, it is the target variable that will be evaluated. Please note that an integer with a value of zero is not the same as NULL.

Examples

Example 1

{def $my_variable=3}
 
{if $my_variable|is_null()}
    It is NULL.
{else}
    It is not NULL.
{/if}

The following output will be produced: "It is not NULL.".

Example 2

{def $my_variable=3}
 
{if is_null( $my_variable )}
    It is NULL.
{else}
    It is not NULL.
{/if}

The following output will be produced: "It is not NULL.".

Example 3

{def $a=3
     $b='Mobile instrument.'}
 
{if $a|is_null( $b )}
    It is NULL.
{else}
    It is not NULL.
{/if}

The following output will be produced: "It is not NULL.".