Beefy Boxes and Bandwidth Generously Provided by pair Networks
Think about Loose Coupling
 
PerlMonks  

Re: Re: undef'ing @arrays caveat

by dmmiller2k (Chaplain)
on Apr 20, 2002 at 22:50 UTC ( #160817=note: print w/replies, xml ) Need Help??


in reply to Re: undef'ing @arrays caveat
in thread undef'ing @arrays caveat

True, and in fact if you undef @array the effect is identical. See my node, above.

Replies are listed 'Best First'.
Re: Re: Re: undef'ing @arrays caveat
by Juerd (Abbot) on Apr 20, 2002 at 23:01 UTC

    True, and in fact if you undef @array the effect is identical.

    Try using Devel::Peek. undef @array sets MAX to -1, @array = () does not. Or use Benchmark and find out that undef @array is about twice as fast. The effect is the same, but internally, there's something entirely different going on.

    - Yes, I reinvent wheels.
    - Spam: Visit eurotraQ.
    

      Granted. But besides the speed issue, the result is effectively the same.

      In the case of undef @array, @array does not actually get undefined (i.e., it still exists), just emptied, however more efficiently than with @array = ().

        @array does not actually get undefined

        undef can only un-define scalars, because only scalars can be not-defined. Hashes and arrays are emptied, subs and globs are destroyed. I think the manual is not clear enough about this.

        - Yes, I reinvent wheels.
        - Spam: Visit eurotraQ.
        

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://160817]
help
Chatterbox?
and all is quiet...

How do I use this? | Other CB clients
Other Users?
Others rifling through the Monastery: (8)
As of 2018-01-17 10:08 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    How did you see in the new year?










    Results (198 votes). Check out past polls.

    Notices?