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What is the difference between $message and $$message?
PHP Interview Questions and Answers
(Continued from previous question...)
What is the difference between $message and $$message?
Anwser 1:
$message is a simple variable whereas $$message is a reference variable. Example:
$user = 'bob'
is equivalent to
$holder = 'user';
$$holder = 'bob';
Anwser 2:
They are both variables. But $message is a variable with a fixed name.
$$message is a variable who's name is stored in $message. For example,
if $message contains "var", $$message is the same as $var.
(Continued on next question...)
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