## Example

`

     mixed variant_add ( mixed $left , mixed $right )

`

## Description

Adds left to right using the following rules (taken from the MSDN library), which correspond to those of Visual Basic: Variant Addition Rules If Then
Both expressions are of the string type Concatenation
One expression is a string type and the other a character Addition
One expression is numeric and the other is a string Addition
Both expressions are numeric Addition
Either expression is NULL NULL is returned
Both expressions are empty Integer subtype is returned

## Return Values

Returns the result.