PHP表达式：为什么var_dump（false <-1）= true？

Question

Can you please explain how PHP execute this code and the result is true?

var_dump( (false < -1) ); //bool(true)

Answer 1

False is boolean type, and from PHP maunal:

-1 is considered TRUE, like any other non-zero (whether negative or positive) number!

Resource: http://php.net/bool