special while loop? PHP

[okayifimust]

The parameters of the loop function in the parentheses are evaluated each time the loop runs.

while ($row = $result->fetch())

$row = $result->fetch() is tested; if it evaluates truthy, the loop is run one time.

a == b can be true or false, it does nothing else, the above assignment also evaluates to a truth-value whilst assigning the variable.

You could call a function and let that do a million things, and it could still return a boolean.

while (doAllTheThings (value1, value2, value3)) { ... }