PHP7 <=> 'Spaceship' Operator Explanation, Questions & Answers

PHP7, which will come out in September this year will introduce a new type of operator, called 'SpaceShip' operator. This <=> operator will offer combined comparison in that it will -

• Return 0 if values on either side are equal
• Return 1 if value on the left is greater
• Return -1 if the value on the right is greater

The rules used by the combined comparison operator are same as the currently used comparison operators by PHP viz. <, <=, ==, >= and >. Those who are from PERL or RUBY programming background may already be familiar with this new operator proposed for PHP7.

Here's a simple example -
//Comparing Integers

echo 1 <=> 1; //ouputs 0
echo 3 <=> 4; //outputs -1
echo 4 <=> 3; //outputs 1

//String Comparison

echo "x" <=> "x"; // 0
echo "x" <=> "y"; //-1
echo "y" <=> "x"; //1

...and so on.