comment on

Given that undef is designed to do that job, I wonder why you would use anything else?

@a = (); clears the scalars and sets the notional size as reported by scalar @a or $#a to zero, but it does not release or reduce the basic AV. Thus it hangs on to some memory even though the array is 'empty';
```
use Devel::Size qw[ total_size ];;
@a = 1 .. 1e6;;
print total_size( \@a );;
32000176

@a = ();;
print total_size( \@a );;
8000176
[download]
```

splice @a; has the same, hang-on-to-some-of-it effect as @a = ();

@a = 1 .. 1e6;;
print total_size( \@a );;
32000176

splice @a;;
print total_size( \@a );;
8000176
[download]

undef however, does a proper job and releases (almost) all the associated memory back to the process pool:
```
@a = 1 .. 1e6;;
print total_size( \@a );;
32000176

undef @a;;
print total_size( \@a );;
176
[download]
```
All it retains the essential head structure.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: arrays : splice or undef ? by BrowserUk
in thread arrays : splice or undef ? by JockoHelios

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