undef is how Perl designates that a variable is uninitialized. undef $var is how you declare that the variable is no longer initialized. $var= undef does the same thing.

If you try to disinguish 'undef' from 'uninitialized', then you'd need a new way to deinitialize variables and an alternative for defined that would tell you if a variable was initialized.

undef and defined are just Perl's methods of introspection about whether a variable is initialized. It is good that you can explicitly mark a variable as uninitialized and that you can programmatically check for initialization. Marking a variable as uninitialized can look like initializing the variable.

I agree that using "uninitialized" instead of "undefined" in error messages is unfortunate. But they mean the same thing in Perl.

- tye        

In reply to Re^3: A bit more clarity on uninitialized value in string ne (init vs def) by tye
in thread A bit more clarity on uninitialized value in string ne by wolis

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