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# Operators
## Basic
Various basic operators can be applied directly to variable values.
## Examples
```smarty
{$foo + 1}
{$foo * $bar}
{$foo->bar - $bar[1] * $baz->foo->bar() -3 * 7}
{if ($foo + $bar.test % $baz * 134232 + 10 + $b + 10)}
...
{/if}
{$foo = $foo + $bar}
```
> **Note**
>
> Although Smarty can handle some very complex expressions and syntax,
> it is a good rule of thumb to keep the template syntax minimal and
> focused on presentation. If you find your template syntax getting too
> complex, it may be a good idea to move the bits that do not deal
> explicitly with presentation to PHP by way of plugins or modifiers.
## Ternary
You can use the `?:` (or ternary) operator to test one expression and present the value
of the second or third expression, based on the result of the test.
In other words:
```smarty
{$test ? "OK" : "FAIL"}
```
will result in OK if `$test` is set to true, and in FAIL otherwise.
There is also a shorthand `?:` operator:
```smarty
{$myVar ?: "empty"}
```
will result in 'empty' if `$myVar` is not set or set to something that evaluates to false, such as an empty string.
If `$myVar` is set to something that evaluates to true, the value of `$myVar` is returned. So, the following will
return 'hello':
```smarty
{$myVar="hello"}
{$myVar ?: "empty"}
```
## Testing for null
If "something that evaluates to false" is to broad a test for you, you can use the `??` (or null coalescing) operator
to trigger only if the tested value is undefined or set to null.
```smarty
{$myVar ?? "empty"}
```
will result in 'empty' if `$myVar` is not set or set to null.
If `$myVar` is set to something that evaluates to anything else, the value of `$myVar` is returned. So, the following will
return an empty string (''):
```smarty
{$myVar=""}
{$myVar ?: "this is not shown"}
```
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