, a comparison operator
for numbers, similar to the string comparison operator 'cmp
<=> and cmp return:
These returns are the same as strcmp
The <=> operand is known as the spaceship operator, for reasons that should be obvious if you have seen Star Wars.
), "<=>" means double implication
, an implication
that goes both ways. In other words,
A <=> B
means the same as
A => B and B => A
"<=>" is often read as "if and only if".