php variable scope -

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i'm confused php variable scope. such as:

while(true){     $var = "yes , test!";   }   printf($var)

the $var defined in while statement scope , how outside it's scope ? , can't find explanation on document .

i wonder how php deal it's scope .

if while(true) not out of while, wouldn't matter. if have real expression, (this useless example, know)

$i=0 while($i<10){     $var = "yes , test!";     $i++;  }   printf($var);

will work. there no special "while" variable scope, printf print string. check : http://php.net/manual/en/language.variables.scope.php


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