How to implement self-increment and self-decrement of PHP Boolean values

This article mainly introduces the implementation method of self-increasing and self-decreasing PHP Boolean values. It has a certain reference value. Now I share it with you. Friends in need can refer to it.

In the morning and After the business requirements battle was over, I was about to open the group to see if any experienced drivers had checked out the car. Suddenly I saw some messages from @E五九天II

He discovered that PHP The Boolean value of , no matter how many times it is incremented, the final output is 1

This is more interesting~

Self-increment and self-decrement, what is the difference between $a and $a We all know that

a means to take the address of a, increase the value of a in the memory, and then put the value in the register
a means to take the address of a, load the value of a into the register, and then add The value of a in the memory

I opened an editor to confirm the result

$a = true;
var_dump(--$a);
echo PHP_EOL;
echo $a;
$b = false;
echo PHP_EOL;
var_dump(++$b);

The final input result of the operation is as follows

bool(true)
1
bool(false)

I found that the result was not quite what I expected. PHP did not do anything for the auto-increment operation of Boolean values. Processing, and the reason why it is 1 after incrementing is because we use echo to output, resulting in the bool being forced to

to query the official documentation of PHP, but unexpectedly there is a line of obvious prompts

Note : Increment/decrement operators do not affect boolean values. Decrementing a NULL value has no effect, but increasing NULL results in 1.

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