Re: standard perl routine

You need to use use.

use POSIX qw[ pow ];

print pow(2,3);
8

print pow( 1000, 0.33333333333333333 );;
10
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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?

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

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

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Re^2: standard perl routine by davido (Cardinal) on Apr 30, 2006 at 07:38 UTC
If I understand the docs correctly, POSIX automatically exports pretty much everything except for subroutine names that conflict with Perl built-ins. If you wish to protect your namespace, the easiest way to override this unfortunate behavior is to invoke POSIX like this: `use POSIX (); # Import nothing. print POSIX::pow( 2, 3 ); # Use the fully-qualified name.` [download] Dave	[reply] [d/l]
Re^3: standard perl routine by BrowserUk (Patriarch) on Apr 30, 2006 at 08:01 UTC
Specifying an import list explicitly prevents POSIX from importing anything other than the functions you specify: `c:\test\546536>p1 print scalar keys %main::;; ## Before use POSIX main has how many glob +als? 67 use POSIX qw[ pow ];; print scalar keys %main::;; ## and after is has 72 Terminating on signal SIGINT(2) c:\test\546536>p1 $h{ $_ }++ for keys %main::;; ## Record what we have before use POSIX qw[ pow ];; $h{ $_ }++ for keys %main::;; ## Again after print for grep{ $h{ $_ } == 1 } keys %h;; ## Display the differences _<c:/Perl/lib/auto/POSIX/POSIX.dll XSLoader:: POSIX:: pow _<POSIX.c` [download] Two 'private' paths, two new namespaces and one new function (pow) in main. Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal? "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^4: standard perl routine by davido (Cardinal) on Apr 30, 2006 at 08:03 UTC
Ah, so it does. Good call. The same mechanism that makes `use POSIX ();` (ie, import an empty list) exclude all, also makes `use POSIX qw/pow/;` exclude all others. Dave	[reply] [d/l] [select]