http://www.perlmonks.org?node_id=1084010

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

Hi monks, I was wondering if there is any options to define the variable name of for example a string when the script runs. For example something like this

$number =1;
$name.$number= 'hey';

so the variable with the string 'hey' would be $name1

is this or something similar possible
i appreaciate your answers
thanks!

Replies are listed 'Best First'.
Re: define variable name on the way
by amon (Scribe) on Apr 27, 2014 at 18:10 UTC

    There is a feature similar to this in Perl, but this is considered to be a very bad idea, because it makes code utterly unmaintainable. Use arrays instead.

    my $index = 0;
my @array;
$array[0] = "hello";
$array[1] = "world";
print "$names[0] $names[1]"; #=> "hello world"

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    You can also use variables for the 0 or 1: “my $index = 0; $array[$index] = "hello"”

    Or you could use hashes

    my $index = 0;
my %hash;
$hash{greeting} = "hello";
$hash{name} = "world";
print "$hash{greeting} $hash{name}"; #=> "hello world"

    [download]

    Again, you could also use variables:

    my $key = "greeting";
$hash{$key} = "hello";

    [download]

    Edit: properly escaped square brackets

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[d/l]
[select]

      The canonical explanation why you shouldn't use variables as variable names was given by MJD in the varvarname emails.

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      Also, the above formatting got b0rked. The second paragraph should be:

      You can also use variables for the 0 or 1: “my $index = 0; $array[$index] = "hello"”

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        Because you posted as a registered user, you can un-b0rk your own original post by editing it, in this case by adding  <code> ... </code> tags. Please see Writeup Formatting Tips and Markup in the Monastery.

        Update: If you edit or update one of your posts, please add a brief notation of the edit and its nature.

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[d/l]
Re: define variable name on the way
by NetWallah (Canon) on Apr 27, 2014 at 18:12 UTC
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Re: define variable name on the way
by Laurent_R (Canon) on Apr 27, 2014 at 21:45 UTC
    The bottom line is that symbolic references can almost always be replaced with an hash. I once tried symbolic references because I had the feeling that it was difficult to do otherwise, only to find out finally that I only needed a hash of hashes to solve my problem. Having gone through that dilemma, I think I can find a better solution for just about any problem, I can't think of a real reason where symbolic references would really make sense.
[reply]
Re: define variable name on the way
by bart (Canon) on Apr 28, 2014 at 20:28 UTC
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