Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris
 
PerlMonks  

Re: Re: Re: Re: NEWBIE Brain Teaser

by hiroki (Novice)
on Apr 16, 2001 at 19:29 UTC ( #72839=note: print w/replies, xml ) Need Help??


in reply to Re: Re: Re: NEWBIE Brain Teaser
in thread NEWBIE Brain Teaser

i am not a "more monkish Monk", but i did get curious about this behavior of foreach. This is an alias (example modified from _Advanced Perl Programming_ (O'rielly) by Sriram Srinivasan):
$a = 10; # saclar a @a = (1, 2, 3); # array a *b = *a; # aliases b to a $a++; # increments $a :) $b++; # same as saying $a++ print "$b, $a"; # prints: 12 12 @b[0] = 4; # same as saying $a[0] = 4
as you can see, the aliasing on line 3 makes any manipulation of $b, @b or %b manipulate $a, @a, %a respectively. hope this helps and is not too confusing. if i'm wrong, tell me :)

Replies are listed 'Best First'.
Re (tilly) 5: NEWBIE Brain Teaser
by tilly (Archbishop) on Apr 16, 2001 at 19:53 UTC
    That aliasing command relies on typeglobs to work.

    Therefore it will only work with global variables. (ie you must localize with local, not my.) I stay away from that except when it really doesn't make sense not to. :-)

    The mostly widely used form of that kind of aliasing in modern Perl is for exporting symbols using Exporter.

    FWIW one goal for Perl 6 is to kill typeglobs entirely. The functionality should be available, but by a different mechanism...

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://72839]
help
Chatterbox?
[james28909]: i forgot how to link my scratch pad
[Lady_Aleena]: [pad://]
[james28909]: my scratchpad
[james28909]: and like i say, is just an example, not working code, but hopefully you understand what i mean. :)
[james28909]: and like i say, it would be alot of work to get around renaming 3 subs haha
[Lady_Aleena]: Well, you would have to add the file munging and a lot more.

How do I use this? | Other CB clients
Other Users?
Others exploiting the Monastery: (9)
As of 2017-05-24 05:20 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?