Question

perl <=>是什么

perl <=>是什么

Answer 1

<=>是 Spaceship operator
太空船操作符:三向的比较数字操作符

$a<=>$b 这个操作符比较两个数字，返回-1,0,1。
返回1 $a>$b
返回0 $a=$b
返回-1 $a<$b

比如：
$a = 5 <=> 7; # $a is set to -1
$a = 7 <=> 5; # $a is set to 1
$a = 6 <=> 6; # $a is set to 0

Answer 2

比较大小，$num1<=>$num2,是指比较两个数的大小，如果$num1>$num2返回1；如果$num1=$num2返回0；如果$num1<$num2返回-1