Re: [PHP] distinguish between null variable and unset variable

On Wed, Jan 21, 2009 at 20:27, Jack Bates <ms419@xxxxxxxxxxxxxx> wrote:
How can I tell the difference between a variable whose value is null and
a variable which is not set?

Unfortunately, in PHP - like other languages - you can't.

A variable is considered to be null if:
* it has been assigned the constant NULL.
* it has not been set to any value yet.
* it has been unset().

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</Daniel P. Brown>
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