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while loop in php with assignment operator

the code I'm looking at does this...

while ($info=mysql_fetch_array($data_jurisdiction))
{
//some stuff
}

I'm wondering what does this while statement do? it has an assignment operator within it, so as long as $info gets assigned a value other than false, this code will execute?

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[... S]o as long as $info gets assigned a value other than false, this code will execute?

Quite, yes. Even there is an assignment operator within that expression, the expression itself still stands for a value. In this case the result of the whole expression is equal to the assignment to $info. In other words: The expression is the same as $info or the expression has been assigned to $info - the last variant is perhaps the best description.

So now whenever $info equals to true, the code block inside while will be executed.

Keep in mind that the comparison is a loose comparison. So not only false but as well NULL or an empty array will stop the execution of the inner code-block.


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