比较数组与int在PHP中

Question

I'm reading through the drupal_bootstrap code at: https://api.drupal.org/api/drupal/includes%21bootstrap.inc/function/drupal_bootstrap/7 to try to understand how to bootstrap drupal code. I have experience in other languages but not php. This line of code below puzzles me, because $phases is an array, and everything else is int. What does it mean when it compares array with an int?

while ($phases && $phase > $stored_phase && $final_phase > $stored_phase) {
      $current_phase = array_shift($phases);

Thanks!

Answer 1

In php basic comparison, an array with elements== True and an empty array== False .
array_shift() reduce the size of array.

So, in your example, the loop reduce the size of $phases until the $phases is empty.
(better: until $phases is empty or one of the other conditions are False )

Edit:

There is not a comparison between array and integer, the condition is:
ARRAY IS NOT EMPTY AND INT > INT AND INT > INT.

Edit 2:

Please note that there are a sort of incongruity in php type juggling comparison:

array() == False
''      == False
0       == False

but:

''      == 0
array() != ''   <------ !!!!
array() != 0    <------ !!!!

Answer 2

it does not compare array to int.
the first part of the condition where it uses $phases just checks that it has a value.

Definition of bootstrap in Computing:

a technique of loading a program into a computer by means of a few initial instructions which enable the introduction of the rest of the program from an input device.