Strict, cant use string as hash ref

westy032001 has asked for the wisdom of the Perl Monks concerning the following question:

Helo Guys/Gals please could you help explain this error
"Can't use string ("CPU_USER_jwesvsf7") as a HASH ref while "strict refs" in use"
and if possible suggest an alternate way of doing it. Problem code:

use strict;

    my $server="jwesvsf7";
    my $timestamp = "123433";
    my $attribute="CPU_USER";
    my $hashname =$attribute."_".$server;
    print "$hashname";
       
     ${$hashname}{key} ="value" ;
[download]

many thanks. Thank you all for your responses!!

Comment on Strict, cant use string as hash ref Download Code

Replies are listed 'Best First'.
Re: Strict, cant use string as hash ref by moritz (Cardinal) on Dec 09, 2009 at 12:15 UTC
Instead of storing the name of a hash in a variable, use a nested hash: `use strict; my %hash; my $server="jwesvsf7"; my $timestamp = "123433"; my $attribute="CPU_USER"; my $key =$attribute."_".$server; $hash{$key}{key} = 'value';` [download]	[reply] [d/l]
Re: Strict, cant use string as hash ref by JavaFan (Canon) on Dec 09, 2009 at 12:09 UTC
Well, you have a string "CPU_USER_jwesvsf7", inside a variable "$hashname", which you are treating as it were a (name of) a hash. That's a symbolic reference, which 'use strict' prevents you from using. Either don't use symbolic reference, or disable strict.	[reply]
Re: Strict, cant use string as hash ref by roboticus (Chancellor) on Dec 09, 2009 at 13:17 UTC
westy032001: If you use moritz' solution, be sure to examine how you're using your hash. If you find yourself breaking up your current key on the '_' character later on, you might find it better to go ahead and have another key level or two, like: `my ($server,$attribute) = ('jwesvsf7', 'CPU_USER'); $hash{$attribute}{$server}{key} = "value";` [download] ...roboticus	[reply] [d/l]


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