What three-mesh operator

In most programming languages, there are three-mesh operators: In this form, let's take a look at the three-mesh operator instance.

$safe = $input? $input: ' Default ';

This code is a bit redundant in some places, so the median value is already optional. Now just use the ifsetor syntax, just like the following code.

$safe = $input?: ' Default ';

One of the common operations in processing input data is to provide a default value using the three-mesh operator when the input data does not exist or the checksum fails. You've probably seen code similar to the following.

haha simple, good crap don't say more recommend my good friend?